Thank you for viewing. This is an Arca-Swiss compatible clamp, perfect for small tripods and ball heads. Similar sized clamps are available from brands like Leofoto, but the MENGS clamp has an Arca-Swiss compatible plate on the bottom, allowing you to rotate the orientation 90 degrees when combined with your existing clamp. This is useful for expanding the mounting options when using lens supports, etc., so it's convenient to have one. This is a used item, so please refrain from purchasing if you are looking for a perfect condition item or are overly concerned about minor details. (Search terms) Quick release clamps Quick release clamps (in Japanese) Ball head Ball head (in Japanese) Arca-Swiss Arca-Swiss compatible Quick shoe Quick release Tripod Monopod Traveler Small