The ring secures your lens to the camera's tripod

Having a thumbscrew control the ring makes it easy to adjust the tripod ring on the go

The ring adds stability to your camera and lens. Due to its weight, when the lens is mounted with a camera on a tripod, the center of gravity is shifted to the lens. The ring attaches to the tripod and can be shifted to any position on the lens, ensuring the weight is evenly distributed

Having the camera secured with a ring around the lens makes it possible to rotate the lens between landscape and portrait modes without removing the camera from the tripod. The position of the camera distinguishes portrait or landscape mode, not the position of the lens. The friction thumbscrews can then be tightened to secure the camera in the desired position. When not needed, the ring can be rotated to an out of the way position

The hinge provides the ability to keep the lens attached to the camera while disconnecting the lens from the tripod