●??【Size Information 】Ball size: 1"/ 254mm,Length: 6"/ 152mm. ●??【Ball Head with Protection Ring】:1 ball head made by corrosion resistant anodized aluminum alloy with rubber O-Ring Friction Gaskets, avoid friction during connection and make the connection more stable. ●??【Hollow Design】The hollow design makes it lighter and reduces resistance when used underwater. The weight is only 2.8oz(80g),the buoyancy almost completely offsets its gravity. ●??【Free Extension】8 Double 1 inch Ball Arm supports to connect strobe or video light, Freely adjust the angle to get the best lights angles to take the best photo you want. ●?? 【Center distance between two balls】:2.9"/76mm Arm as a bridge to connect underwater tray/handle to underwater strobe/video light.