Immersive Sound: Active noise cancellation for an immersive audio experience. Transparency Mode: Allows you to hear and connect with the world around you. Sweat & Water Resistant: IPX4-rated for sweat and water resistance during non-water sports and exercise. Adaptive EQ: Automatically tunes music to the shape of your ear for optimal sound quality. Easy Setup: Seamless setup for all your Apple devices with quick access to Siri by saying "Hey Siri". Battery Life: Wireless Charging Case provides more than 24 hours of battery life. Compatibility Requirements: Requires an iCloud account and compatible with macOS 10.14.4, iOS 12.2, iPadOS, watchOS 5.2, or tvOS 13.2 or later. ***Good working condition, however, left earbud looses battery more quickly. Works great, does occasionally have a small issue with active noise cancellation that is minimal. Might be fixed with changing the bud