ISO High Test Chain uses high tensile strength carbon steel that provides a greater strength-to-weight ratio than proof coil chain. ISO short pitch link makes it more flexible and ideally suited as a windlass chain. Each link is proof tested and calibrated. Sold in Standard Pack lengths only. Not currently sold by the foot. Grade 43 Hot-Dip Galvanized High Test Windlass Chain Specifications Size Inside Link Length MWL Weight Standard Pack 1/4" .84" 2,600lb. .75lb./ft. 800' 5/16" 1.03" 3,900lb. 1.07lb./ft. 550' 3/8" 1.22" 5,400lb. 1.52lb./ft. 400' 7/16" 1.4" 7,200lb. 2.07lb./ft. 300'