Good battery and unfortunately firmware unknown. The Sony WF-1000XM5 Noise Cancel Wireless Earbud Replacement Silver (LEFT) is a high-quality, wireless earbud designed for an in-ear fit. With Bluetooth connectivity and a rechargeable battery, this earbud offers convenience and flexibility. It features active noise cancellation, volume limitation, and a built-in microphone for hands-free calls and music playback. The replaceable ear tips, waterproof design, and sweat-proof materials ensure durability and comfort for long periods of use. Perfect for those looking for a reliable and feature-packed wireless earbud option.