Zacuto Z-Finder Mounting Frame for DSLRs with Battery Grips is required when mounting a Z-Finder to the 3" LCD screens of small-body cameras--from the Canon 5D Mark II to the Nikon D90--equipped with battery grips. This longer frame attaches to a required Gorilla Plate using two thumb screws; then, with the frame's rubber edges pressing snugly against the LCD screen, the Z-Finder can snap quickly into the frame & be just as easily removed. Works with Z-Finder Pro 2.5x, 3x, & Jr. (Gorilla Plate not included with Z-Finder Jr.--must be purchased separately) made from aircraft aluminum Non-stick rubber coating seals off light & prevents scratching of camera