Truly wireless, open-back Bluetooth earbuds offer immersive stereo sound with Bose Immersive Audio, Bluetooth 5.3 connectivity, IPX4 water resistance, and simple one-button controls for all-day listening while staying aware of your surroundings. Bose Ultra Open Earbuds feature an open design with a secure, comfortable fit designed to stay in place all day, plus a built-in microphone for easy call and media control. Open-back design helps you hear your surroundings alongside your music Bose Immersive Audio for a more engaging listening experience Bluetooth 5.3 wireless connection with AAC and SBC support Built-in microphone and controls for play/pause, skip tracks, volume, and answer/end calls Up to 7.5 hours of playtime (up to 4.5 hours with Immersive Audio) and up to 48 hours on standby IPX4 water resistance for everyday use Reliable, everyday portable headphones with long battery life and intuitive controls for uninterrupted listening.