• Model:HS4_hdt

Duct Humidistat - HS4_hdt

£ 254.02 (excl. VAT)

£ 304.82 (inc. VAT)

Electronic inline Duct humidistat to monitor humidity levels of 30-100 %RH suitable for switching extract fans, alarms or de-humidifiers

~ Size 108mmx72mmx72mm - Probe length 225mm.
~ Set of volt free changeover contacts
~ Rating 5Amp, 2A inductive.

3 x HCFC 1.7 - Reversible Speed Controller for HCF sweep fans1 x VLTM102 5.5kW 11.7A IP66 (400V)2 x JSR 200 Painted RAL50181 x CBP-10/82 x FU 22 25 Frequency Inverter1 x FRQ-10A V2 Inverter Speed controller1 x Helios TSD 3.0 Transformer Speed Control (400v)1 x Helios - FIUK-11KW 24.0A - FREQUENCY INVERTER1 x Circular Ceiling Diffuser - TST 1251 x FU 075 04 Frequency Inverter (IP20)1 x Frequency converter RUCK - FU 075 211 x FU 22 04 Frequency Inverter2 x ELTA - Three Phase Transformer 3amps1 x ELTA - Three Phase Transformer 10amps1 x NKS-D swirl diffuser v-300 x 300mm2 x Elta 10 Amp Electronic single phase speed controller.2 x FU 15 16 Frequency Inverter2 x Elta Variable Speed Drive IP66 - 5.5KW2 x Elta Variable Speed Drive IP66 - 1.5KW1 x Frequency converter RUCK - FU 075 202 x Elta Variable Speed Drive IP66 - 0.75KW1 x FU 075 52 Frequency Inverter (IP20)1 x Curved Blade Grille 600x600 (2way blow)2 x Round ceiling diffuser 400mm2 x ELTA - Single Phase Transformer 2amps1 x Circular Ceiling Diffuser - TST 2001 x Balance S Diffuser - NO RING - 125mm1 x PCA Diffuser - PCA-3153 x Round ceiling diffuser 200mm1 x 5-Speed Controller for use with Elta SAX Classic Fans1 x Balance S Diffuser - NO RING - 100mm3 x EC6H - Reversible Group Fan Electronic Controller1 x Circular Ceiling Diffuser - TST 1603 x Electronic extractor fan speed controller - FSC 1.54 x AIRVENT speed control - AIR4019611 x ELTA - Single Phase Transformer 12amps1 x Round ceiling diffuser 350mm2 x Airvent ceiling fan controller2 x Elta 3 Amp Electronic single phase speed controller.1 x ELTA - Single Phase Transformer 8amps1 x ELTA - Single Phase Transformer 16amps2 x Round ceiling diffuser 300mm3 x Elta 3 Amp Electronic single phase speed controller with TK1 x EFSC-3N- Single Phase Speed Control1 x Elta 2 Amp Electronic single phase speed controller.2 x Elta 6 Amp Electronic single phase speed controller.1 x EFSC-6N- Single Phase Speed Control1 x PCA Diffuser - PCA-2503 x COM-33 x Remote Timer Control - 13511 x ELTA - Single Phase Transformer 10amps3 x Run On Timer - 5s - 4hrs - RT5A1 x Time Delay Unit - DT20B3 x Multi Input Run On Timer - 0 - 20min - CFCU3 x Push Timer Switch - ZA43 x 7 Day Programmable TIMECLOCK2 x Speed Controller - REB51 x TTC-2000 Three phase electric heater controller3 x ACOAS/ AC/EC Auto Changeover 8Amp3 x ACO8AC/EC AutoChangeover panel1 x Elta ACO Panel 149-ACO14E1 x EC-Vent control board1 x CONTROL ECOWATT - Basic1 x S & P Aluminium Axial Fan Louvre Shutter - PER-CR- 6301 x EM30-24 Electro-Mechanical Control Panel1 x ACO 149-ACO1/EDV1 x S & P Aluminium Axial Fan Louvre Shutter - PER-CR- 5001 x Easy-fix termination kit - High Rise Ventilator - EFT1 x EC-Vent Room Unit1 x U-EK plastic housing IP65 - for use with the U-EK230E Motor Protection3 x Systemair Save Connect 2.0 Internet Module1 x Elta ACO Panel 149-ACO18B3 x Transformer Speed Control - RTRE- 1.5Amp1 x EM30-24 Control Panel Commissioning Service1 x Elta Wall Cowl SWC56/631 x GRA-100 External Grill by S&P1 x Elta Wall Cowl SWC35/401 x Elta Wall Cowl SWC25/311 x Elta Wall Cowl SWC45/501 x Elta Louvre Shutter - 400mm1 x S & P Aluminium Axial Fan Louvre Shutter - PER-CR- 7101 x Jet Cowl - 315mm1 x Egg Crate Grille with Dust panel filter 1 inch- 595x5951 x Single Deflection Grille 400mm with OBD damper1 x Non Vision 150mm x 150mm (Air Transfer) Grille - With Flange - MILL FINISH3 x Mini Diffuser - 100mm1 x Egg Crate Grille with Dust panel filter 1 inch- 300x3001 x Economy Airvent 150mm Fan With Pullcord & Shutters1 x Economy Airvent 100mm Fan with Timer1 x Same Day Shipping Surcharge - City Sprint2 x DV-ROF-V-225 Roof mounted unit2 x DPD 12PM Delivery Surcharge1 x Northern Ireland Pallet Surcharge1 x DPD 10:30AM Delivery Surcharge1 x Manrose T12 STANDARD Transformer- T12S1 x 18M - 80mm PVC flexible ducting1 x Economy Airvent 150mm Fan1 x DV-ROF-V-315 Roof mounted unit1 x Manrose 150mm - XF150BHP1 x Manrose 150mm - XF150BP1 x D2E-146-AP47-751 x Biflow SB250-CON4-1 - High Temperature Bifurcated Fan1 x Control board kit Smarty 4X P 1.1 F2 Fan 230V1 x DPD SATURDAY Delivery Surcharge1 x Impeller Side Guard - 800mm1 x Economy Airvent 100mm Fan with Timer/Humidistat/Pullcord1 x HPA Heavy Duty Flexible Ducting - HPA300-FD51 x CAB-150 ECOWATT Energy Efficient Acoustic Box Fan2 x HIMF - Mixed Flow Fan 125mm Inline Fan1 x HQS Bathroom Axial Flow Fan - 125mm1 x CTVT/4-400 High Temp Roof Fan - 51369260001 x AW Sileo EC Plate Axial Fan - Three Phase - 1000mm2 x HIMF - Mixed Flow Fan 100mm Inline Fan1 x Elta - SMT 125 Mixvent Inline Fan - Clearance Stock Line1 x AW Sileo EC Plate Axial Fan - Three Phase - 800mm1 x AL 315 EC 01 AXIALINE - High Performance Long Cased Axial Fan2 x Transformer Speed Control - RTRE- 7.0Amp2 x MTS10- extractor fan 3 step switch1 x CBM 9/7 4 Pole 373watt VR (Open Motor)1 x CBM 10/10 - 373watt - 6 Pole2 x Capacitor 2uf for use with the EBM A4E range1 x Small Centrifugal Fans CBM/2-133/190 185w1 x Fresh Air control carbon filter - 125mm1 x Manrose Auto Shutter - XF150AP1 x Maico EN31- Wall Mounted Fan1 x CRBB/3-250/084M EC 2H01 x CAB-315 ECOWATT Energy Efficient Acoustic Box Fan1 x CBM 12/9 CM/AL 1100W 6PT - Closed Motor1 x LF-ME04F071LC3AC1 x CAB-355 ECOWATT Energy Efficient Acoustic Box Fan1 x AW Sileo EC Plate Axial Fan - Three Phase - 630mm1 x CRBB/3-190/060M EC 1HO MP - External Rotor Motor Radial Fans1 x Small Centrifugal Fan - CBM/4-160/150-125 W2 x EBM-Papst D3G133-BF05-14 Double inlet1 x CRBB/3-160/052M EC 1H0 MP - Radial Impeller - 160mm1 x G2E160−AL19−56 FLUE FAN1 x Vent Axia ACM 100 T (Timer Model) inline mixed flow duct fan2 x Vent Axia ACM 150 T (Timer Model) inline mixed flow duct fan3 x Remote controller FLEX - for VEKO INT1 x S&P MULTI-REG EC FAN CONTROLLER / INTERFACE1 x Transformer 5 Speed Controller - ATC1-2TK2 x Helios TSW 7.5 Amp Transformer speed controller2 x Transformer 5 Speed Controller - ATC1-4TK1 x Transformer 5 Speed Controller - ATC1-10TK2 x Transformer 5 Speed Controller - ATC1-8TK1 x REU 1.5amp Speed control - Two Speed Five-Step Transformer - Trickle and Boost3 x Helios TSW 3 Amp Transformer speed controller2 x Helios TSW 0.3Amp Compact Transformer speed controller1 x Vent Axia ACM 150 inline mixed flow duct fan1 x RTRD - Three Phase Speed Controller - 2 Amp3 x Three Phase Transformer controllers - RMT 1.5 Amp2 x RDS 11 Helios Transformer Controller With Motor Protection2 x Helios TSW MCB Amp Transformer speed controller1 x Helios TSW 1.5 Amp Transformer speed controller2 x Helios TSW 10 Amp Transformer speed controller3 x CS2 Current Switch2 x Vent Axia ACM 200 inline mixed flow duct fan4 x Vent Axia ACM 125 inline mixed flow duct fan1 x MV-B Dual Switch for use with Helios HQW plate fans,2 x TG-K Duct temperature sensor3 x DEF-140T Inlet Guard for the CBT-100N2 x Single phase speed controller by auto-transformer - RMB 3.5 Amp1 x Two Speed Switch - REGUL-21 x Elta 6 Amp Electronic single phase speed controller with TK1 x Single phase speed controller by auto-transformer - RMB 10.0 Amp2 x Envirovent G4 Filter - SL-G4/F72 x REE-1 Electronic Speed Controller1 x Speed Controller - REB32 x MWS 1.5 – Transformer Controller With Motor Protection1 x WS - Reversing Switch from Helios Fans1 x EBM-Papst D2E097-BK76-98 Double inlet1 x CMT-2 200/80 1.1KW - Single inlet centrifugal fan direct driven2 x Envirovent Silent MV160/100T Mixvent - Timer Model - 100mm - (5 year warranty)1 x ERR 31/1 Centrifugal inline fan4 x Transformer (silent) speed controller - RE 3.0 Amp2 x Helios HQW-200/4 - IP552 x Speed Controller - REB101 x Transformer (silent) speed controller - RE 1.5 Amp3 x CBS-60 Outlet Flange for CSB/CBT-602 x KMBI 180 Connector rectangular/circular to install on the discharge of CMT2 x Speed Controller - REB1-N1 x MTV-1/010 Controller 0 to 10V+2 x Multiflow SMB550/4-1AC1 x REE-2 Electronic Speed Controller1 x REB-CVF 0-10v Controller1 x Transformer (silent) speed controller - RE 5.0 Amp4 x MTP 10, 10K, Speed control1 x Commercial Single or 3 phase Fan Reversing Switch - RS12 x FAST-TRACK RANGE 75mm - Click Ring (1 bag of 10)3 x PIR Sensor - PIR21 x Multileaf Volume Control Dampers -500/500 Rectangular Flanged2 x Vent Axia ACM 125 T (Timer Model) inline mixed flow duct fan1 x REU 3amp Speed control - Two Speed Five-Step Transformer - Trickle and Boost1 x TDP-D Pressure Sensor with Display1 x REU 7amp Speed control - Two Speed Five-Step Transformer - Trickle and Boost1 x Temperature Controller - EDTW1 x MWS 5 – Transformer Controller With Motor Protection Unit1 x Transformer speed controller - ATC1 - 1.5 Amps2 x Vent Axia ACM 100 inline mixed flow duct fan1 x RTRD - Three Phase Speed Controller - 14 Amp1 x RTRD - Three Phase Speed Controller - 4 Amp1 x Single phase speed controller by auto-transformer - RMB 1.5 Amp1 x TEM 035 - 5 Speed Transformer Speed Control1 x TD EVO-100 PF ECOWATT - Environmentally Friendly Energy Efficient Inline Fan1 x ERR 20/1 Centrifugal inline fan2 x Helios HQW-630/4 - IP551 x FAST-TRACK RANGE 90mm - Adaptor For Distribution Box1 x Speed Controller - REB61 x Rectangular Airbrick Adaptor1 x FAST-TRACK RANGE 90mm - Click Ring (1 bag of 10)1 x ELM 18 EX Flexible Cuff for ERM 182 x Skyflow SSR Horizontal Roof Cowl SSR31/35B2 x Speed Controller - REB12 x Transformer Speed Control - RTRE- 5.0Amp3 x PIR Sensor - PIR41 x Control switch - CR1501 x RR EC 160 Centrifugal inline fan - Energy Efficient Motor2 x Speed Controller - REB81 x Elta Variable Speed Drive IP66 - 2.2KW2 x Silent 100 Window Kit - windowS2 x SG-200 Fan Guard for the HQW 2001 x Helios PU10 Speed Potentiometer (Flush Mounted)1 x RSK355 - Back Draught Shutter2 x Quietflow SQS400-1ECL - Centrifugal Box Fan2 x TD Mixvent 800/200 EEXEIIT32 x Vent Axia Silent 100T (TIMER)2 x Speed Controller - REB2.5-N1 x Elta Variable Speed Drive IP66 - 7.5KW1 x Transformer Speed Control - RTRE- 3.0Amp2 x Helios HQW-250/4 - IP551 x Skyflow SSR Horizontal Roof Cowl SSR80B1 x RTRD - Three Phase Speed Controller - 7 Amp1 x Temperature Fan Speed Controller - ATCP4-FLS1 x DEF-800AN2 x CMT-2 225/090 1.1KW - Single inlet centrifugal fan direct driven2 x UB47- Universal Insulated Terminal2 x CBA-60 Inlet Flange for CBT-601 x DEF-CBM-RE-7 - Protection Guard1 x Bathroom Fan -Envirovent- Silent 100 T (Timer Model)2 x DDMP 09/09 Mounting Flange1 x ELM 25 EX Flexible Cuff for ERM 252 x DDMP 12-12 3F 1810W M6A4 DG01 x Elta Variable Speed Drive IP66 - 4.0KW1 x Speed Controller - REB162 x TUNE-R-200-3-M4 - Control Damper3 x QPTW 250C Acoustic Twin Fan with Controller1 x Compact SCD450/4-1AC1 x Contactor Interface Station - CI92 x Elta - Room Sensor - Temp/Humid/C021 x Elta Variable Speed Drive IP66 - 0.37KW (1ph to 3ph)3 x Silentub - STUB 1001 x Compact SCD500/4-3AC1 x GENIOX 11 Internal Mounted Unit2 x ELM 20 EX Flexible Cuff for ERM 221 x 220x90mm Insulated Rectangular Horizontal 90° Bend1 x GXC6EC - High Performance Extract Fan1 x 204x60mm Insulated Rectangular Horizontal 45° Bend1 x 220x90mm Insulated Rectangular Vertical 45° Bend1 x KKS 100 silencer-section - For use with the MUB 100 size Fans.1 x 220x90mm Insulated Rectangular Horizontal 45° Bend1 x SAVE VSR 300 heat recovery unit1 x BDS 800 RA b/d shutter1 x FAST-TRACK RANGE 75mm - Adjustable Air Restrictor1 x DA9/9-NT1 x Electrostatic Precipitator - 1H x 3W1 x 204x60mm Insulated Rectangular Vertical 45° Bend2 x CO2 Room Sensor - CO2-R1 x GX6EC - High Performance Extract Fan1 x RTRDU 3 Phase Trickle & Boost 5 Step Speed Controller - 2 Amps1 x RSK400 - Back Draught Shutter1 x Double Inlet Forward Curved Centrifugal Fans - FDA-450-CM1 x Duct Termination with Mesh - 355mm1 x 204x60mm Insulated Rectangular Horizontal 90° Bend2 x CBM Low Pressure Centrifugal Fan - CBM 10/10 4 Pole 550watt CVR1 x KBA- Inlet Mounting 2801 x Quietflow SQS100-1ECL - Centrifugal Box Fan1 x DVG-H 560D4/F400 IE2 - Smoke extract roof unit1 x CSB-60 Centrifugal fan3 x VEKA INT 2000/15.0-L1 EKO1 x LFBR 315 G4 - Helios Inline Filter Box - 315mm1 x 110 x 54mm Round to Rectangular Adaptor - Long1 x LFBR 160 G4 - Helios Inline Filter Box - 160mm1 x Singleflow SSDL315-1EC1 x Helios RR-250-C Centrifugal inline fan1 x Duct Termination with Mesh - 710mm2 x TD160-NT Mixvent - 100mm - TD160 Timer2 x Round ceiling diffuser 250mm1 x Duct Termination with Mesh - 100mm2 x AXC TP - 100mm Plastic Centrifugal Inline Fan1 x 204x60mm Insulated Rectangular Vertical 90° Bend1 x CBP-18/18-RC Belt Driven Centrifugal Fans2 x VTR 500 STD Filter Kit1 x IR24-P - Presence detector2 x CFI In-line 150 - Carbon Filter1 x DVV 560D4-XM/F4002 x Vertical Cowl and Fan (Single Phase) - RAV400-4-11 x Ancillary Pack for SLC-800 for 4 Pole and SLC-800/6B-3AC1 x VKS 355-500 Automatic shutter2 x Biflow SB400-CON2-3 - High Temperature Bifurcated Fan1 x CBM 7/7 147w 4P RE-VR1 x DEF-900AN3 x WSD 100 (1060x1060x70)2 x CBA-100 Inlet Flange for CBT-1001 x Duct Termination with Mesh - 560mm1 x Clearflow CF Roof Mounted Vertical Discharge Centrifugal Fan - CF400/4-1AC - Single Phase3 x KBA- Inlet Mounting 2252 x Helios ESA-1 Surface mounted Speed Control 1amp1 x Elta Variable Speed Drive IP66 - 2.2KW (1ph to 3ph)3 x 100mm Round Connector with Damper1 x Flat Roof Terminal -OFT 5 - Asphalt3 x CBB-60N Centrifugal1 x ACO3TO-ADS-VFC-7.1A2 x CBT-130N Centrifugal ATEX II 3D ExtD 125*C2 x Duct Termination with Mesh - 150mm2 x CBM Low Pressure Centrifugal Fan - CBM 9/7 4 Pole 373watt CVR1 x Comefri - TLZ 225 R - High Performance Scroll Fan1 x Clearflow CF Roof Mounted Vertical Discharge Centrifugal Fan - CF450/4-1AC - Single Phase1 x Quietflow Twin SQTDCV250-1ECL1 x DVG-V 560D4/F400 IE23 x CBM Low Pressure Centrifugal Fan - CBM 12/12 6 Pole 736watt CVR1 x Duct Termination with Mesh - 450mm1 x DDMP 07/07 Mounting Flange1 x Vent Axia Trickle & Boost Switch1 x Binks Bullows - Spray Booth Filter2 x Potentiometer EGH 01 - for DDMP Fans1 x Comefri - TLZ 450 R - High Performance Scroll Fan1 x KBA- Inlet Mounting 1802 x RUCK MTP 20, 10K, Speed control1 x TD Mixvent 1100/250 EEXEIIT31 x TUNE-R-160-3-M0 - Control Damper (NO ACTUATOR)1 x Spiral end cap - 355mm2 x DDMP 10-08 FLANGE1 x Duct Termination with Mesh - 500mm1 x CCpro 40 (1CC9402) Long Casing Extension1 x Twinflow STDL315-1EC1 x Comefri - TLZ 560 R - High Performance Scroll Fan1 x AKOR Mounting Plate for GD model(VIM166423)1 x CBB-80N Centrifugal1 x Clearflow CF Roof Mounted Vertical Discharge Centrifugal Fan - CF400/4-3AC - Three Phase1 x Duct Termination with Mesh - 250mm2 x CBP-9/7-RC2 x Universal Pipe Fixing Clip2 x CBS-100 Outlet Flange for CBT-1001 x TUNE-R-160-3-M2 - Control Damper1 x CBM 9/7 4p 420W RE-VR2 x Elta HXP 800mm 6-Pole (Three Phase)2 x CAD-COMPACT 900 ADVANCED N8 - MVHR unit2 x SPI-200 C Iris damper2 x Chaysol DA 9/9 3 speed1 x Compact SCD450/4-3AC1 x Quietflow SQSDCV500-1ECL - Centrifugal Box Fan1 x Envirovent 4 Way Remote Control Switch - SWHBKRF-42 x Temperature Fan Speed Controller - ATCP4-WMS1 x Transformer 5 Speed Controller - ATC1-12TK1 x Isolator Switch - ISOSW3 x Insulated extract Plenum 8+13 x Insulated extract Plenum 6+12 x KMBI 225 Connector rectangular/circular to install on the discharge of CMT1 x MWS 3 – Transformer Controller With Motor Protection2 x TEM 075 - 5 Speed Transformer Speed Control1 x Vent Axia T-Series Controller3 x KMBI 315 Connector rectangular/circular to install on the discharge of CMT2 x Vortice Quadro Micro 100 I - Standard Version3 x TG-K3/NTC10-01 - Duct temperature sensor1 x Isolator Switch - EFF-ISO1 x Transformer Speed Control - RTRE- 12.0Amp3 x TUNE-R-200-3-M1 - Control Damper2 x Helios HQW-315/4 - IP552 x KMBI 250 Connector rectangular/circular to install on the discharge of CMT2 x Skyflow SSR Horizontal Roof Cowl SSR31/35BS1 x CBM 9-9 550w 4P VR (Open Motor)1 x DDMP 09-09 3F 2130W M6A4 DG02 x TUNE-R-250-3-M1 - Control Damper3 x TUNE-R-100-1-M1 - Control Damper2 x CBT-100N Centrifugal1 x ENV 100 12v transformer SELV2 x TUNE-R-100-2-M5 - Control Damper2 x TUNE-R-250-1-M2 - Control Damper3 x DDMP 10-08 3F 2210W M6A4 DG01 x TUNE-R-100-2-M1 - Control Damper3 x TUNE-R-200-3-M2 - Control Damper2 x CBM 12-12 1100w 6P Three Phase2 x Elta Standard Ambient Flexible Connector - 560mm2 x KBA- inlet mounting flange for CRMT 2251 x CBM Low Pressure Centrifugal Fan - CBM 10/10 4 Pole 550watt VR1 x TUNE-R-200-3-M5 - Control Damper3 x CMT/4-315/130-4KW - Single inlet centrifugal fan direct driven3 x SD-MUB Vibration pad set2 x TUNE-R-200-3-M0 - Control Damper (NO ACTUATOR)1 x CMT/4-280-115 2.2KW - Single inlet centrifugal fan direct driven ( LG-90)2 x TUNE-R-180-2-M5 - Control Damper1 x Flakt Woods ME 1.6 speed controller 6.0amp - EA9011591 x KAD-355-F400 Rectangle Flexible Connector2 x Helios HQW-355/4 - IP551 x Polyurethane Foam Media - 10PPI - Filter Media Sheets - Size: 2000mm x 1000mm2 x TUNE-R-160-1-M1 - Control Damper2 x CMT-2 250-100 3KW - LG0 Single inlet centrifugal fan direct driven2 x CMT-2 250-100 3KW - RD270 Single inlet centrifugal fan direct driven2 x KBA- Inlet Mounting 3152 x Flakt Woods ME 1.3 speed controller 3amp - EA9011581 x TUNE-R-250-3-M0 - Control Damper (NO ACTUATOR)1 x Elta SCP400/4-1AC - IP552 x TUNE-R-250-1-M1 - Control Damper2 x KBA- Inlet Mounting 2501 x TUNE-R-160-2-M3 - Control Damper2 x DDMP 12-12 3F 5700W M6M0 DG73 x TUNE-R-200-3-M3 - Control Damper2 x TUNE-R-315-3-M1 - Control Damper2 x Flakt Woods ME 1.1 speed controller 1amp - EA9011571 x TUNE-R-250-2-M2 - Control Damper1 x DDMP 10-10 1F 1000W M6A2 DA51 x CMT/4-250-100 1.1KW - Single inlet centrifugal fan direct driven ( LG-90)2 x DDMP 12-09 1F 1800W M6A4 DA81 x SDD-U Anti Vibration Pads1 x Elta SCP500/4-1AC - IP551 x VA 9/2 T - High Temp Axial Fan,2 x CBM Low Pressure Centrifugal Fan - CBM 9/9 4 Pole 550watt 3V (3-Speed)1 x Backdraught Shutters 039-SFSV-63/711 x Quietflow SQSDCV500-3ECL - Centrifugal Box Fan1 x CMT-2 120/50 - 0,09Kw - LG270 Single inlet centrifugal fan direct driven
Reviews
DAOSL Back Draft Damper
DAOSL Back Draft Damper
£ 11.49

Look good, works well, except the shaft of the lanellae cuts...