£39.40

Kidde Twin Pack Kidde Firex KF20 Mains Powered Optical Smoke Alarm with 9V Back Up Batteries | KF2 | 4973

White, KF2 4973

Price data last checked 59 day(s) ago - refreshing...

View at Amazon

Price History & Forecast

Last 32 days • 32 data points (No recent data available)

Historical
Generating forecast...
£39.87 £35.60 £36.53 £37.46 £38.40 £39.33 £40.26 18 January 2026 25 January 2026 02 February 2026 10 February 2026 18 February 2026

Price Distribution

Price distribution over 32 days • 3 price levels

Days at Price
25 days 5 days 2 days 0 6 13 19 25 £36 £39 £40 Days at Price

Price Analysis

Most common price: £36 (25 days, 78.1%)

Price range: £36 - £40

Price levels: 3 different prices over 32 days

Description

Mains-powered optical smoke alarm that can be interlinked with up to 23 other Kidde mains alarms, be they ionisation, optical or heat. Once interlinked, the detection of the relevant danger by an individual unit will sound across all the connected alarms. Optical alarms are for use in escape or circulation routes and in areas where there is a danger of ignition of furniture and surroundings by cigarettes producing slow, smouldering fires. This mains-powered unit should be installed by a qualified electrician and can be used throughout the home, except in the kitchen where a Firex Heat Alarm is recommended. These alarms comply with UK Building Regulations for new housing and associated standards (Grade D BS 5839, Part 6).

Key Features

Mains-powered optical smoke alarm that can be interlinked with up to 23 other Kidde mains alarms, be they ionisation, optical or heat. Once interlinked, the detection of the relevant danger by an individual unit will sound across all the connected alarms.

Interlink with up to 23 Kidde Firex hard-wired alarms – all alarms sound if danger is detected

Mains operation – 9V Alkaline back-up battery supplied as standard

Reduced energy consumption – lower lifetime running costs (* compared to previous Firex alarms)

Combined Test/HushTM button allows regular testing of alarm function and can be used to temporarily silence nuisance alarms

Dust compensation and bug screen – reduces nuisance alarms

Alarm memory – identifies source unit within interconnecting network

Auto reset after activation

Product Specifications

Brand
Kidde
Colour
White
Format
Electronics
Domain
Amazon UK
Listed Since
02 July 2014

Barcode

No barcode data available

Similar Products You Might Like

Kidde Firex KF20 Optical Smoke Alarm - Mains Operated with Battery Back Up
97% match

Kidde Firex KF20 Optical Smoke Alarm - Mains Operated with Battery Back Up

Kidde

£19.97 01 Dec 2025
New Kidde FireX KF20 Mains Powered Optical Smoke Alarm Fire Detector with 9V Battery Backup
96% match

New Kidde FireX KF20 Mains Powered Optical Smoke Alarm Fire Detector with 9V Battery Backup

iXium

£22.14 23 Feb 2026
Replacement for Kidde KF10 Mains Powered Smoke Alarms
95% match

Replacement for Kidde KF10 Mains Powered Smoke Alarms

Kidde

£21.96 21 Feb 2026
Kidde 2030-DSR Battery Powered Optical Smoke Alarm for Home | 9V Replaceable Battery (Included) | 10 Year Sensor Life and Fully Certified
95% match

Kidde 2030-DSR Battery Powered Optical Smoke Alarm for Home | 9V Replaceable Battery (Included) | 10 Year Sensor Life and Fully Certified

Kidde

£11.99 17 Feb 2026
Deta 1163 Optical Smoke Alarm 240V with 9V Replaceable Battery Back Up (White)
94% match

Deta 1163 Optical Smoke Alarm 240V with 9V Replaceable Battery Back Up (White)

DETA

£29.94 18 Feb 2026
FireAngel Mains Smoke Alarm - SW1-R Mains Powered Optical Smoke Detector with Backup Battery - Wired, Interlinked Smoke Alarms for Home with Test Button and LED Indicators - White
94% match

FireAngel Mains Smoke Alarm - SW1-R Mains Powered Optical Smoke Detector with Backup Battery - Wired, Interlinked Smoke Alarms for Home with Test Button and LED Indicators - White

Fireangel

£17.09 19 Feb 2026
FireAngel Mains Smoke Alarm - SW10-EUT Mains Powered Optical Smoke Detector with Replaceable Long Life Backup Battery - Wired, Interlinked Smoke Alarms for Home with Test Button and LED Indicators
94% match

FireAngel Mains Smoke Alarm - SW10-EUT Mains Powered Optical Smoke Detector with Replaceable Long Life Backup Battery - Wired, Interlinked Smoke Alarms for Home with Test Button and LED Indicators

Fireangel

£38.99 18 Feb 2026
Firexo fxo Interlinked Smoke Alarm for Home&Office (Pack of 2) -Wireless Optical Smoke Detector Alarm with 10 Year Tamper Proof Battery -Can be used with Carbon Monoxide & Heat Alarm (sold separately)
93% match

Firexo fxo Interlinked Smoke Alarm for Home&Office (Pack of 2) -Wireless Optical Smoke Detector Alarm with 10 Year Tamper Proof Battery -Can be used with Carbon Monoxide & Heat Alarm (sold separately)

Firexo

£68.66 17 Feb 2026
Kidde 10SCO Smoke & CO Alarm with Voice Alerts - 10 Year Warranty
93% match

Kidde 10SCO Smoke & CO Alarm with Voice Alerts - 10 Year Warranty

Kidde

£24.90 16 Feb 2026
FireAngel FA3820-T2 10 Year Sealed Battery Alarm Carbon Monoxide & FireAngel Optical Smoke Alarm with 10 Year Sealed For Life Battery, FA6620-R-T2 - Twin Pack , White
93% match

FireAngel FA3820-T2 10 Year Sealed Battery Alarm Carbon Monoxide & FireAngel Optical Smoke Alarm with 10 Year Sealed For Life Battery, FA6620-R-T2 - Twin Pack , White

Fireangel

£58.43 21 Feb 2026
FireAngel Optical Smoke Alarm with 5 Year Replaceable Batteries, FA6615-R-T2 (ST-625 replacement, new gen) - Twin Pack & FA3820 10 Year Sealed Battery Alarm Carbon Monoxide, Clear
93% match

FireAngel Optical Smoke Alarm with 5 Year Replaceable Batteries, FA6615-R-T2 (ST-625 replacement, new gen) - Twin Pack & FA3820 10 Year Sealed Battery Alarm Carbon Monoxide, Clear

Fireangel

Out of Stock 07 Mar 2026
Firexo fxo Interlinked Smoke Alarm for Home&Office (Pack of 3) -Wireless Optical Smoke Detector Alarm with 10 Year Tamper Proof Battery -Can be used with Carbon Monoxide & Heat Alarm (sold separately)
93% match

Firexo fxo Interlinked Smoke Alarm for Home&Office (Pack of 3) -Wireless Optical Smoke Detector Alarm with 10 Year Tamper Proof Battery -Can be used with Carbon Monoxide & Heat Alarm (sold separately)

Firexo

Out of Stock 18 Feb 2026
FireAngel FA3313-SB1-T2 CO & Smoke Alarm Twin Pack & FireAngel Heat Alarm with 10 Year Sealed For Life Battery, FA6720-R (HT-630 replacement, new gen)
93% match

FireAngel FA3313-SB1-T2 CO & Smoke Alarm Twin Pack & FireAngel Heat Alarm with 10 Year Sealed For Life Battery, FA6720-R (HT-630 replacement, new gen)

Fireangel

£40.31 13 Feb 2026
FireAngel FA3820 10 Year Sealed Battery Alarm Carbon Monoxide, Clear & FireAngel Optical Smoke Alarm with 10 Year Sealed For Life Battery, FA6620-R-T2 - Twin Pack , White
93% match

FireAngel FA3820 10 Year Sealed Battery Alarm Carbon Monoxide, Clear & FireAngel Optical Smoke Alarm with 10 Year Sealed For Life Battery, FA6620-R-T2 - Twin Pack , White

Fireangel

Out of Stock 07 Mar 2026
Firexo fxo Standalone Optical Smoke Alarm (Pack of 2)-Smoke Detector with 10 Year Tamper Proof Battery & Loud Alarm -Smoke Alarm for Kitchen, Home, Office &Garage-Easy to Install, No Wire Installation
93% match

Firexo fxo Standalone Optical Smoke Alarm (Pack of 2)-Smoke Detector with 10 Year Tamper Proof Battery & Loud Alarm -Smoke Alarm for Kitchen, Home, Office &Garage-Easy to Install, No Wire Installation

Firexo

Out of Stock 15 Feb 2026
FireAngel FA6620 Optical Smoke Alarm 2-Pack - 10-Year Battery
93% match

FireAngel FA6620 Optical Smoke Alarm 2-Pack - 10-Year Battery

Fireangel

£25.99 14 Apr 2026
FireAngel FA3313-T2 Replaceable Battery Detector Twin Pack Carbon Monoxide Alarm & FireAngel Optical Smoke Alarm with 5 Year Replaceable Batteries, FA6615-R (ST-625 replacement, new gen)
93% match

FireAngel FA3313-T2 Replaceable Battery Detector Twin Pack Carbon Monoxide Alarm & FireAngel Optical Smoke Alarm with 5 Year Replaceable Batteries, FA6615-R (ST-625 replacement, new gen)

Fireangel

£47.24 13 Feb 2026
FireAngel Optical Smoke Alarm with 10 Year Sealed For Life Battery, FA6620-R-T2 (ST-622 / ST-620 replacement, new gen) - Twin Pack, White & FireAngel FA3313-SB1-T2 CO & Smoke Alarm Twin Pack
93% match

FireAngel Optical Smoke Alarm with 10 Year Sealed For Life Battery, FA6620-R-T2 (ST-622 / ST-620 replacement, new gen) - Twin Pack, White & FireAngel FA3313-SB1-T2 CO & Smoke Alarm Twin Pack

Fireangel

£50.59 14 Feb 2026
Firexo fxo Smoke Detector & Carbon Monoxide CO Alarm Value Multipack - 3 Interlinking Unit Home Protection Pack
93% match

Firexo fxo Smoke Detector & Carbon Monoxide CO Alarm Value Multipack - 3 Interlinking Unit Home Protection Pack

Firexo

£113.51 20 Feb 2026
Firexo fxo Smoke Alarm, Heat Detector & Carbon Monoxide CO Alarm Value Multipack - 4 Unit Home Protection Pack
93% match

Firexo fxo Smoke Alarm, Heat Detector & Carbon Monoxide CO Alarm Value Multipack - 4 Unit Home Protection Pack

Firexo

Out of Stock 18 Feb 2026
FireAngel FA3820-T2 10 Year Sealed Battery Alarm Carbon Monoxide & FireAngel Optical Smoke Alarm with 10 Year Sealed For Life Battery, FA6620-R (ST-622 / ST-620 replacement, new gen) , White
93% match

FireAngel FA3820-T2 10 Year Sealed Battery Alarm Carbon Monoxide & FireAngel Optical Smoke Alarm with 10 Year Sealed For Life Battery, FA6620-R (ST-622 / ST-620 replacement, new gen) , White

Fireangel

£53.51 14 Feb 2026
FireAngel HW1-R Mains Powered Heat Alarm for Kitchen with 9V Battery Backup, Hardwired Heat Fire Alarms for Home, Attic, Garage, White, 1-Pack
93% match

FireAngel HW1-R Mains Powered Heat Alarm for Kitchen with 9V Battery Backup, Hardwired Heat Fire Alarms for Home, Attic, Garage, White, 1-Pack

Fireangel

£19.34 24 Feb 2026
FireAngel Pro Connected Smart Smoke Alarm, Mains Powered with Wireless Interlink and 10 Year Life Back-Up Battery, FP1640W2-R, White
93% match

FireAngel Pro Connected Smart Smoke Alarm, Mains Powered with Wireless Interlink and 10 Year Life Back-Up Battery, FP1640W2-R, White

Fireangel

£74.99 14 Feb 2026
FireAngel SB1-R Smoke Alarm - Toast Proof, Optical Smoke Alarms for Home with Replaceable Battery and Test/Silence Button - Early Smoke Detector Fire Alarm - 90 x 35 mm - White
93% match

FireAngel SB1-R Smoke Alarm - Toast Proof, Optical Smoke Alarms for Home with Replaceable Battery and Test/Silence Button - Early Smoke Detector Fire Alarm - 90 x 35 mm - White

Fireangel

£8.79 14 Feb 2026