Overview Product Description 207821 New-No Box; Martin 50BS18-7/8 Sprocket # 50; 18Teeth; 7/8"ID; . Item is New; unused; no factory packaging. Austin Surplus SKU: 207821 Location: 172144-GRG-R16-P20-S05-C-0000522 Product Videos Custom Field MPN 50BS18-7/8 Product Reviews