Lowrider Sprocket Zt7b-a 36t 1/2 X 1/8 Chrome. Lowrider Sprocket Zt7b-a 36t 1/2 X 1/8 Chrome. Lowrider Sprocket Zt7b-a 36t 1/2 X 1/8 Chrome. We carry over 3,000 bicycle parts and accessories. If you have any questions about any of our parts, please send us an email.