This guide is made specifically for MTB bikes with ISCG’05 mount . With simple adjustment with a 4mm Allen wrench, you set the vertical and lateral location of the guide head. The guide head can also be adjust to swing up and out of the way for easy access and maintenance of your chain/crank/ring. Chainguide for ISCG’05 MTB bicycles Short 26T-32T Tall 26T-38T Alloy boom, and inject mold guide head 4mm Allen wrench to adjust vertical, lateral, and guidehead One extraguide head included