The Ring 6-Pack Wireless Contact Sensors for Alarm 2nd Gen are white door sensors designed for indoor use. They are powered by batteries and have a fast response time of 1ms. These sensors are compatible with Amazon Alexa for smart home integration and feature wireless connectivity through Z-Wave protocol. The Ring brand offers a 1-year manufacturer warranty and each sensor has an operating sound rating of 130 dB. Perfect for enhancing home surveillance, these sensors provide added security and convenience with their reliable performance.