Overview Product Description 204503 New-No Box; Martin 40B12SS-20 Sprocket # 40; 12Teeth; 20mm; . Item is New; unused; no factory packaging. Austin Surplus SKU: 204503 Location: 158900-GRG-R01-P05-S05-A-0001752 Product Videos Custom Field MPN 40B12SS-20 Product Reviews