The Novoflex MC 1/4 SPEZIAL MiniConnect Coupling piece is a 1/4 inch connector that features an additional lock to prevent unintentional turning of the camera body. Only for use with cameras or lenses with base plates or tripod connections made of metal. Round shaped and small. Fits to quick release MiniConnect, quick release MiniConnect MR, focusing rack CASTEL-L and focusing rack CASTEL-XL.