These are front dummy axles made for building Schmidt Sl compatible forks (9mmQR). They have one side longer so that the drops are spaced correctly when the insulator and contact plate are installed. I had been using a special shim with my Anvil dummy axle, but it always wanted to get lost, and was just another source of possible error. This is especially noticeable when using disk brake jigs that reference inner drop face. Made here in the PNW by my friends over at https://lichenmfg.com/precision/.