Hs-z, hs-c, hs-vt series chain block: 1.Safety in operation and easy maintenance. 2.High efficiency and sall hand pull. 3.Light weight and easy handing. 4.Fine apperance with sall size. 5.Durability in use Chains: Material:high-quality alloy steel Surface treatment:polishing, galvanized, blcacked Quality grade:g80 g70 g43 Safety factor:min 4