Works for Pro 324 Nozzle but fits many other similar models/sizes. They will work for any nozzle oriface size. This kit provides a 1 replacement black sleeve and 1 replacement bottom cap for the nozzle (*nozzle not included, color of parts may vary black or white but are all the same functionally). These blasters are great, but become $100+ paperweights when the nozzles inside go bad. Not only are these replacements, but an extreme upgrade over the stock parts. A proprietary polymer blend is used, which is much stronger and wear resistant. Simply slide on the new sleeve and press fit on the bottom cap, and you're good to go. There are real life examples of these rebuilt nozzles going well over 100,000 cycles with 0 maintenance on reclaim water. This rebuild kit is not available anywhere else in the world.