Premium Material? This for video doorbell power supply is made of environmentally friendly materials,with good electrical conductivity, transmission stability and durability. It can keep your doorbell running normally, saving time and effort. Safe and Convenient?: Quick fix to the problem of "Low battery", you can charge it directly (plug adapter into outlet and power-up), safe and convenient. With an AC output of 24V/500mA, a perfect tool to meet your needs Installation?This transformer solves the problem of insufficient power and voltage. As long as you install it on your thermostat or doorbell, the installation can be completed in a few minutes, which is very convenient. Continuous Charging?With it, you don't need to take off your device as often as before, just install our product and you can continue to charge. Applicable Products?Suitable for British power cord voltage, Adapter Compatible with All Versions of Video Doorbell and Thermostat for Nest, and can also supply power for other 24V electrical equipment.