[Metal Material]Speed Ring Adapter is made of steel,compact design,sturdy structure [Size Information]outer diameter approx 18.7cm/7.36inch,top inner diameter 9.5cm/3.74inch [Design]Featuring multi mounting slots to accommodate various sizes and shapes of softboxes,including square,rectangular,strip,,and hexagon,providing flexibility for different lighting setups [Feature]Portable Speed Ring Adapter can rotate 360 degrees and locks securely in place for convenient usage [Fitment]Speed Ring can be mounted to studio flash and softbox systems