These are good pinions. The quality is as expected from Tamiya, excellent. The fit and finish of the parts is as expected, brilliant. Do be aware that yes these are 48 pitch, but they are metric. These will ONLY fit tamiya vehicles equipped with 48P metric gears such as their normal electric touring cars like the TL-01 and so forth. These will NOT fit any vehicle using 48P standard. The teeth are slightly too long. Here's a very important tip, if you are going to use the 21 tooth version of this in a TA01/02 or a DF01 with a 74 tooth (standard size) spur gear, do be sure you have the notch on the motor mount pointing DOWN because it seems to work with it up, but you WILL strip out the pinion if you run it this way. I stripped out mine with a Tamiya silver can motor so it's pretty easy to strip one out. As a side thin, the 1:18 scale XTM Rage uses the same pitch on the spur and pinion. Other than that, these are really great products. I give them 5 stars easily.