Using the appropriate tools, gradually tighten the FTTH cable clamp around the fiber optic cable. After tightening, perform a gentle tug test to confirm that the cable is firmly. Fiber optic cable clamps are devices used to secure and stabilize fiber optic cables in a wide range of applications, including telecommunications, data centers, and network systems. These clamps provide a secure foundation for the cables, helping to prevent damage and maintain proper alignment and. Figure 1. The precision V-groove and rubber pad are designed to clamp onto the buffer of single mode or multimode fibers without damaging. You have to take the weight of the wire off the clamp by taking the clamp loose from the wall hook loosen the clamp and readjust it You can then hook it back on the wall.