DSLRKIT Tripod Mount Ring for Tamron SP AF 70-200mm F/2.8 Di LD [IF] MACRO Model A001 The tripod mount ring mount on the tripod, it helps you fix and balance your tele lens which is heavy or long lens hanging off the front of camera Made by metal with very high quality Suitable for Tamron SP AF 70-200mm F/2.8 Di LD [IF] MACRO Model A001