YXLILI Self-Powered Wireless Doorbell with LED Flash

This will reduce it from £25.99 to about £12.99 with Free Delivery.

• Self-powered Doorbell, No Battery Required: With this self-powered doorbell, will no longer worry about when the battery will run out, and you will not miss a friend's knock on the door when the battery is dead. After pressing the push button, it will generate electricity by itself and send a stable signal to the receiver.
• 4 Volume Levels and 38 Chimes: Our Wireless doorbell receiver with 4 levels (including mute) of adjustable volumes from 0 to 85dB, suitable for hearing impaired and adapt to any sleeping needs of the household during the day. The wireless door kit has 38 chimes to choose from, you can change the chimes for holidays or whatever is interesting to you. Flashing light indicators are easy for people to notice.
• Ultra Long Working Distance: This wireless doorbell features up to 150m/500ft wireless range, ensuring you won't miss a visitor, even if you are a few rooms away or on another floor. Waterproof and dust-proof, working temperature ranges from -4℉-140℉ and withstand various harsh weather conditions.