I purchased these stub axles for a slow going project.
i have yet to used them but am very happy with the build quality of them.
they are 17mm shafts which is perfect for using Kart wheels on your project.
Kingpins are 8mm. this might be fine for on-road Karts, but might be an isssue for dirt Karts or project builds, especially if you hit some rough stuff.
i feel the 8mm kingpins and bearings might need to be replaced for 12mm kingpins and bronze bush bearings for any off-road use.
people bend 17mm stubs in accidents, so an 8mm kingpin would just snap.
otherwise, this kit is fantastic. left and right stub, nyloc nuts, wheel spacers and the "C" brakets ready to weld on are all included.
i will return to update this review once the stubs are welded in place and i have the Mower sitting on 4 wheels.