This Manfrotto Photo Clamp can be fixed to surfaces up to 60mm thick. Has 2 x 3/8" male threads for mounting ball head and camera. This replaces the Manfrotto 3287. Attachment: 3/8'' screw; clamp range - max (rectangular tube): 2.36 in.; color: black; diameter: 1.97 in.; material: aluminum; weight: 0.31 lbs.