SB-packed, for assembly and disassembly of FSA Mega Evo, SRAM DUB with 4 mm bearing shell teeth, Shimano TL-FC24, TL-FC25, Hollowtech II and SRAM GXP bottom brackets, for 1/2" socket wrench mount, steel Article version Chainring / Bottom bracket Main color black Suitable for FSA Mega Evo , GXP , Hollowtech II , SRAM DUB 4 mm , Shimano TL-FC24 , Shimano TL-FC25 Use Bottom bracket