Usage Tips:High Compatibility - This 24V transformer is perfect for a variety of devices for Nest, for , and for smart thermostats, as well as Ring, Nest Skybell, and other video doorbells. It ensures your devices always have the power they need for optimal performance. Certified Safety & Performance - With an input of 120V 50/60HZ and an output of 24V 40VA, it provides reliable and continuous power, making it a safe choice for your home's wired systems. Power Multiple Devices - Ideal for upgrading underpowered , our 24V AC Transformer can handle multiple thermostats or doorbells simultaneously. It's the perfect replacement for old , ensuring all your devices function correctly without interruption. Designed for quick replacement and setup, it can be securely mounted in any suitable electrical box within your home. Please note:the physical slightly color difference or difference, does not affect the use, please do not mind, thank you! Colour:Black & Silver Material:Metal+Plastic Package Contents: 1 * Video Doorbell Transformer Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.