A full featured and durable waterproof housing for Sony Alpha 1 and a7S III full frame mirrorless digital cameras. Suitable for scuba, snorkel, surf, pool, and any application in or around the water. The Ikelite system can be expanded for any shooting needs including the addition of an optional M24 accessory port for an HDMI 2.0 external monitor. With the savings over a comparably equipped aluminum system, you can pick up a spare a7S III camera body.