Detailed Product Description Roller chain:1) specificationA series roller chains: 06C, 08A,10A,12A,16A,20A,24A,28A,32A,40A ( Simplex, douplex, triplex)B series roller chains:06B,08B,10B,12B,16B,20B,24B,28B,32B( Simplex, douplex and triplex)2)good material:We all use good material with alloy steel using the advanced heat treatment.3)color:Blue, yellow,natural,black