Ronstan's calibrated turnbuckle are capable of withstanding extreme working loads without compromising weight or aesthetics, making it one of the best rigging products. • Finely calibrated with laser-etched millimeter increments, therefore, reproducing critical rig tension settings is quick and easy • The unique aluminum silicon bronze coupling nut reduces the possibility of galling • Tapered lock nut secures the threaded terminal to the coupling nut and not the turnbuckle body, allowing the wire to rotate freely without losing rig tension and reducing wire fatigue