S3 S-CARGO CHAIN TENSORS. Fitsr Beta, Montesa, Scorpa, and Sherco. Machined from 7075T6 Billet Aluminum and they are an absolutely beautiful, top quality component that looks stunning. Use the small snail, with a short chain, to have the rear wheel close to the engine. Or, use the big snail, with a long chain, to locate the wheel fully rearward for maximum traction.