The plate was bought as a replacement for the TRIOPO Ball Head B-2, the Triopo can not without tools sufficient notice to a Nikon 70-300mm lens to keep with the camera. The Sirui-plate has a U-bolt and if this is not sufficient to attract, the supplied Allen wrench be used. Top I find the two retractable plastic stoppers, extended and the stopper toward the lens mounted hold the camera firmly super. Equipment: Manfrotto 055Pro, Triopo Kugelkop, Nikon D5100, Nikon 70-300mm lenses and more.