The Ecobee SmartSensor Room Temperature Sensor in white are wireless, powered by a 3V button cell battery, and have a 3.5-inch display. They are compatible with various smart home platforms such as eWeLink, Apple HomeKit, Google Home, and Amazon Alexa. These sensors from ecobee are surface-mounted and feature a rectangular shape, making them easy to install and perfect for monitoring room temperatures. With a sleek white design and energy-efficient features, these smart sensors provide accurate temperature readings for optimal home comfort.