FORMSPRAG FSR-8 1.000 Overrunning Backstopping Indexing Clutch

The Formsprag FSR-8/1.000 overrunning, backstopping, indexing clutch is a general‑purpose sprag clutch from the Formsprag FSR family. It uses sleeve‑bearing support and has a 1.000‑inch bore. As an overrunning clutch, it allows the driven member to coast freely when the drive slows, while providing backstop and indexing functionality to resist reverse rotation during start‑ups. The FSR line covers multiple bore sizes and mounting configurations, with the FSR‑8 positioned among mid‑range sizes in the lineup. Common applications include conveyor drives and dual‑drive arrangements, as well as machine‑tool feed or indexing stations that require one‑way torque transmission and holdback during rest or slow cycles.