When you want to fix your old front fork (drum brake). Fits all drum brake models.
Alternative 1 fits Monkey Z50J2 from 1979 and onwards.
Alternative 2 fits Monkey Z50A and Z50J1 from 1969-1978, and all Dax's ST50-ST70 (those with the old model fork not the hydraulic one, which came 1982). Please note that nr 11 and 14 is not standard use with this setup. But since I have found that they help stabilizing the forks.