Angel Barrel Kit
This kit includes 0.685, 0.689, and 0.693 backs, and a 10" barrel tip. The tip is both Apex and Apex 2 ready. This black dust kit works with the Angel A1, A1 Fly, A1 Fly SE, AR:K, and SB.
These back interchange with the standard backs and tips that came stock with the guns listed, so people can choose to use the stock tip with these backs, or vice versa.