#91405 Chain Stopper for chain 9mm - 13mm / 3/8" – 1/2"Works with your anchor rollers to take the tension off the windlass by locking the chain. Handles 9 - 13 mm (3/8” – 1/2") chain. Included a convenient foot tab for safe and easy operation. Mounted with 4 screw holes to increase breaking strength. Made in 316L mirror polished stainless steel.Breaking Load: 2500 kg (5,500 lbs.)Fits Chain Size: 9-13 mm (3/8" – 1/2")