Thank you for viewing. This new float arm combines an aluminum hollow body and carbon fiber to increase strength and buoyancy. By giving the arm itself positive buoyancy, the underwater weight of the housing set can be reduced. It is 22cm long and 5cm in diameter. I have taken it underwater a few times, but I am selling it because I no longer need it due to a system change. It currently sells for nearly 20,000 yen. Please confirm the buoyancy characteristics yourself. It is compatible with housings from Nauticam, Sea&Sea, and INON products, as well as fisheye products. Those looking for underwater housings, underwater strobes, clamps, underwater arms, underwater lights, underwater grips, etc., are also welcome.