Applicable: Threaded BB central axis, ISCG03/ ISCG05 general, 32T-38T Chainring. 3 M6x8 Chain guide screw. 3 M6x12 Adapter screw. 3 M6x6 Adapter screw. Premium material: the chain guide adopts high-strength aluminum alloy with CNC machined and heavy-duty nylon.