JT Sprockets JT is one of the biggest and most popular aftermarket sprocket brands in the world Front sprockets are made from extremely strong SCM420 chromoly steel alloy, and the rear sprockets are made from ultra-durable high carbon C49 steel. The end result is high quality, hard wearing sprockets. We are a well known and long established UK based motorcycle parts supplier with an excellent reputation for delivering high quality motorcycle parts, backed by industry leading customer service. Images The main image in all of our chain & sprocket listings is a generic image. Please refer to the rest of the images in the listing for specific product information.