SKU: 639643203

Kidde Sentry 2x KF21R Optical Smoke & 1x KF31R Heat Alarm Kit Mains Powered with Sealed-In Rechargeable Battery Back-Up c/w Quick Fit Base

$136.99 $152.21
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Description

Kidde Sentry 2x KF21R Optical Smoke & 1x KF31R Heat Alarm Kit Mains Powered with Sealed-In Rechargeable Battery Back-Up c/w Quick Fit BaseKidde Sentry 2x KF21R Optical Smoke & 1x KF31R Heat Alarm Kit with Rechargeable Lithium Battery Back Up The Kidde Sentry Alarm Kit combines two KF21R Optical Smoke Alarms and one KF31R Heat Alarm to provide dependable whole home fire detection for residential properties. Designed for mains powered installation, each alarm features a sealed rechargeable lithium battery back up and can be interconnected with up to 23 compatible Kidde FIREX alarms. This

Kidde Sentry 2x KF21R Optical Smoke & 1x KF31R Heat Alarm Kit with Rechargeable Lithium Battery Back-Up

The Kidde Sentry Alarm Kit combines two KF21R Optical Smoke Alarms and one KF31R Heat Alarm to provide dependable whole-home fire detection for residential properties. Designed for mains-powered installation, each alarm features a sealed rechargeable lithium battery back-up and can be interconnected with up to 23 compatible Kidde FIREX alarms.

This advanced alarm system delivers reliable smoke and heat detection across hallways, bedrooms, living spaces, kitchens and loft areas, helping properties comply with UK Building Regulations while enhancing occupant safety.

Each alarm is supplied with Kidde’s Quick-Fit Slide-On Base for faster installation, while integrated cable management ensures neat and secure wiring. The 150mm flared base plate also provides a clean finish during retrofit installations.

Kit Contents

  • 2 x Kidde KF21R Optical Smoke Alarms
  • 1 x Kidde KF31R Heat Alarm

KF21R Optical Smoke Alarm Features

The Kidde KF21R optical smoke alarm is designed to detect slow, smouldering fires caused by electrical faults, furniture or cigarettes. Ideal for escape routes and living areas, the optical sensor provides dependable early warning protection.

  • Mains-powered optical smoke alarm with sealed rechargeable lithium battery back-up
  • Optical sensor with dust compensation and bug screen
  • Interconnects with up to 23 Kidde FIREX alarms
  • Alarm memory identifies the activated alarm
  • Combined Test/Hush button
  • Auto reset after activation
  • Tamper-resistant locking mechanism
  • Suitable for hallways, bedrooms, lofts and living rooms
  • BSI certified to BS EN14604:2005
  • 10-year warranty

KF31R Heat Alarm Features

The Kidde KF31R heat alarm is designed for kitchens, garages and loft spaces where smoke alarms may be unsuitable due to cooking fumes, dust or steam. The thermistor heat sensor provides reliable heat detection while reducing nuisance alarms.

  • Mains-powered heat alarm with sealed rechargeable lithium battery back-up
  • Thermistor heat sensor for reliable heat detection
  • Interconnects with up to 23 Kidde FIREX alarms
  • Alarm memory identifies the activated alarm
  • Combined Test/Hush button
  • Auto reset after activation
  • Tamper-resistant locking mechanism
  • Ideal for kitchens, garages and loft spaces
  • BSI certified to BS 5446 Part 2:2003
  • 10-year warranty including battery

Key Benefits

  • Complete smoke and heat alarm system for residential properties
  • Sealed rechargeable lithium battery back-up for maintenance-free protection
  • Interlinked alarms provide whole-home warning when danger is detected
  • Quick-Fit bases for fast and efficient installation
  • Integrated cable management for neat wiring
  • Suitable for compliance with UK Building Regulations
  • Grade D1 domestic fire alarm system solution
  • Fully compatible with Kidde FIREX smoke, heat and CO alarms

Technical Specifications

KF21R Optical Smoke Alarm

  • Model: KF21R
  • Power Supply: 230V mains with sealed rechargeable lithium battery back-up
  • Sensor Type: Optical
  • Alarm Volume: 85dB minimum at 3 metres
  • Dimensions: 150mm x 150mm x 53mm
  • Weight: 260g
  • Operating Temperature: -10°C to +40°C
  • Warranty: 10 Years

KF31R Heat Alarm

  • Model: KF31R
  • Power Supply: 230V mains with sealed rechargeable lithium battery back-up
  • Sensor Type: Thermistor heat sensor
  • Alarm Volume: 85dB minimum at 3 metres
  • Dimensions: 150mm x 66mm
  • Weight: 245g
  • Operating Temperature: -10°C to +40°C
  • Warranty: 10 Years including battery

Please Note: Alarms are supplied individually within the kit. Installation should be carried out by a qualified electrician.

Downloads

KF21R Data Sheet:
Download KF21R Data Sheet

KF31R Data Sheet:
Download KF31R Data Sheet

KF21R Instruction Manual:
Download KF21R Instruction Manual

KF31R Instruction Manual:
Download KF31R Instruction Manual

Shipping Notes
  • Free Standard Shipping on $100+ Orders to the USA.
  • Except Preorder products are shipped in 48 hours.
  • Delivery to the USA:
  1. Standard Shipping : 3-10 business days
  • If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
  • We offer a 30-day return/exchange service after receiving.
  • Final sale items are not eligible for returns or exchanges.
  • To process your return/exchange, please contact us at [email protected]
  • Please click here for more details>>> Return & Exchange Policy
SKU: 639643203

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J
Just Me
Bozeman, US
★★★★★ 5
Room Divider That Gives Instant “This Is a Separate Space Now” Energy
Size: 3 Panel 12FT W
The Siebwin 3 Panel Folding Privacy Screen is surprisingly effective at changing the feel of a room without requiring construction, commitment, or somebody yelling about load bearing walls. The 12 foot width gives a substantial amount of coverage, making it useful for creating privacy, dividing open areas, blocking visual clutter, or setting up temporary sections within larger rooms. This saved us a ton of time and money in our new studio and enabled us to create a kitchen and office in one room. The wider feet make a huge difference because flimsy room dividers that collapse every time someone exhales too aggressively are deeply annoying. This one feels more stable and grounded once positioned. The folding design makes it easy to move around or adjust depending on the space, and it folds down relatively compactly when not in use. It is basically the introvert curtain wall of dreams. The material has a clean, neutral look that blends well into different room styles without screaming “temporary office cubicle panic.” It works well for apartments, studios, shared spaces, dressing areas, or simply hiding the mountain of chaos you swear you are going to organize tomorrow. Practical, portable, and refreshingly easy to use without turning setup into a three hour emotional event.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 16, 2026
S
Skeetre
West Palm Beach, US
★★★★★ 4
It's 2 panels holding 1 big privacy screen. Can't use as 2 separate 4' panels, but works great.
Size: 2 Panel 8FT W
This 2 panel privacy screen works well. Assembly was very straight forward, with easily labeled tubes. My son and I had it together in about 10 minutes, which was probably 3 minutes of me telling him to quit playing around and hand me the parts. It feels very sturdy, not likely to fall over or anything. The material fits well, with the Velcro being very strong. Measurements are all very accurate, with all pieces attaching properly. We have a similar privacy screen at work that we have to try and stretch out because the top and bottom Velcro doesn't fit quite right... this model does not have any issues though. The material is thin and light weight, but solid black so that you can't see anything through or behind it. I definitely think it's a great deal for the money. What I think would have given it 5 stars though, is if you had 2 totally separate 4' panels instead of 2 panels with one big screen. It really wouldn't cost any extra to make it so that the screen was in 2 pieces and you could use it as 2 separate panels instead of having to use it as one big panel. It says 2 panel folding privacy screens, but it's really one big one that folds in the middle.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on May 25, 2026
E
Verified Purchase
Edith Mastrianni
Phoenix, US
★★★★★ 5
8 panel Room Divider is excellent quality
The GoFlame 8 Panel Room Divider is made with excellent material and the seller of this Divider is totally customer friendly. I highly recommend this company and this Divider if you are shopping for a room divider.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on April 25, 2026
J
Verified Purchase
✧˖° Jeanne Lee ✧˖°
San Leandro, US
★★★★★ 5
A Versatile and Elegant Solution for Room Separation
I recently purchased the GOFLAME 8 Panel Room Divider, and I'm thoroughly impressed with its quality and design. This room divider is not only a decorative element, but it also provides a practical solution for creating distinct areas within a room. Here's why I'm giving it a 5-star review: Enhanced Privacy Space: The 6 ft tall room divider is perfect for creating a private space within a larger room. It's ideal for my home office, and I can use it to separate my workspace from the rest of the room. The screen also creates a cozy and intimate atmosphere, making it perfect for relaxing or reading. Hand-woven Texture: The unique hand-woven texture of the room divider adds an element of sophistication and warmth to my room. The intricate craftsmanship is impressive, and it exudes artisanal charm. I love the way it looks, and it's become a conversation piece in my home. Built with Strength: The solid wood frame is sturdy and well-constructed, providing reliable support for the room divider. I'm impressed by the attention to detail and the quality of the materials used. Foldable Design and Easy Storage: The foldable design of the room divider makes it easy to store when not in use. I can simply fold the panels flat and store them away, which is convenient and space-saving. The metal hinges that connect the panels are also sturdy and well-made. No Assembly Required: I was pleasantly surprised to find that the room divider requires no assembly. I simply took it out of the box and set it up, and it was ready to use. The smooth woven surface is also easy to clean and maintain. Overall Impression: I'm thoroughly impressed with the GOFLAME 8 Panel Room Divider. It's a stylish and functional solution for creating a private space within a larger room. The hand-woven texture and solid wood frame add an element of sophistication and warmth, and the foldable design makes it easy to store. I
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on September 14, 2024
B
Verified Purchase
Beverly D Clark
Natrona Heights, US
★★★★★ 5
Quality product !
This is a quality lightweight room divider.! Actually is the second one of this type that I have bought. If you have an area that you just want to close off from the rest of the room, these work perfect!!!
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on October 14, 2025

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