A21 medium base smart LED bulb is part of the Philips Hue smart lighting ecosystem and is compatible with the Hue Bridge to unlock all the light bulb's features (sold separately) 1600lm brightness rating is vibrant and inviting and can change colours for extra ambience Bluetooth connectivity makes wireless control of the light bulb a breeze ZigBee app gives you fine-tuned command over the light strip's functions 25000 hour life bulb expectancy gives you plenty of time to enjoy the illumination Works with Apple HomeKit, Google Assistant, Amazon Alexa, and Microsoft Cortana voice assistants for flexible and easy commanding options