8-122 Insulated Swivels, with Half Link & Coupling Self Locking Hook.绝缘旋转钩（带半环和连接型自锁钩）8-132 Insulated Swivels, with Shank & Coupling Sling Hook绝缘旋转钩（带直柄和连接型吊钩）8-121 Insulated Swivels, with Shank & Coupling Self Look Hook绝缘旋转钩（带直柄和连接型自锁钩） 安全荷重设计系数4:1测试通过，根据EN1677:2000条件测试Design factor 4:1 proof tested and certified Tested acc to EN 1677:2000 绝缘旋转环（Insulaed Swivels），能防御1500伏高压电，带检测证书，设计用于在对悬空货物进行电焊操作时，保护高空起重机。Inpidually tested to resist 1500 Volts insulated with Test Certificate.Design for protection of overhead crane during welding operations on suspended loads.