For Coleman EX-U mini bike. Believe me . Buy them and throw away the crappy factory brake pads. They make such an improvement that you will wonder why you waited so long to put them on. Comes with two springs. They are so easy to install. Each of your Chinese 8 inch mini bikes uses the same size brake pads. With or without grooves. Serious. You'll see how bad the factory brakes are after you put these EBC brakes on. Cheaper than medical bills because your fucking factory brakes didn't work. EBC brakes are better for your muscle car or pickup truck, especially when towing a trailer. BUY THIS. The EBC office is at Patrick's in Las Vegas if you have any questions.