Often times changes in technology are hard to keep up with. We just get that new product, and all of a sudden it's not compatible with the next, greatest thing. One example of that situation is if you have any older Lefty "SL" or Lefty "50" hubs (Basically anything prior to 2016) but have upgraded your current fork to a Lefty 2.0 or Lefty SuperMax. You'll notice it simply doesn't fit in some instances. Yes - There are brake adapters available, but those are sometimes not in stock, or not available for a specific configuration. We have created a solution in the form of a Hub Spacer, CNC'd to our exact specifications which will turn any SL hub into a 2.0/SuperMax hub. We commissioned these from a Government Contractor that is ISO 9001 certified, and they are machined from 6061 T6 Aluminum, with Fillets added to the backside for strength. They are then hard anodized and laser etched. They require longer rotor bolts, which are included.