This is a 12mm wheel reamer used on front and rear 1/8 on-road wheels that are a little too tight to slide on the quick release axles. Most rims are close in size but just a tiny bit to o tight. This reamer makes it much easier to slide the wheels on/off.
Reamer comes with a 3D printed handle and flute cover that screws on for a single self contained unit. These are not super expensive reamers but I have been using the exact same one for a few years now, and it has maintained it edge.
