Classic design armrest. SPEC: For Ø31.8 handlebar with TUB-S OPTION: ALLOY EXTENSION TUBE:TUB-S, TUB-J, TUB-S1, TUB-S2 3K OR UD CARBON EXTENSION TUBE:TUB-S-C, TUB-J-C, TUB-I-C, TUB-S2-C