When installing Z32 drum brakes with S13 or S14 hubs onto our rear drop knuckles, our spacer will let you avoid needing to buy Z32 hubs (that have the extra material built in at the spacer area for the drum anchor pin). Our newest knuckles have the M8p1.25 threaded hole already machined into the casting for your convenience. Our cast knuckles sold prior to July 2018 may not already have a trheaded M8 hole. If so, just follow the process shown in the gallery to mark the hole, drill and tap for the M8 set screws included with these gold anodized aluminum spacers.