Does the strength sign chain block specification: the 0.5T chain block, the 1T chain block, the 1.5T chain block, the 2T chain block, the 3T chain block, the 5T chain block, the 10T chain block, the 20T chain block, the 30T chain block, the 50T chain block are complete, do the strength sign chain block are one kind of use simple, the versatility, carries the convenience the manual hoisting machinery, may use in the factory, the mine, agricultural, the electric power, the building production construction, the wharf, the dock, the warehouse machine installment, the cargo hoisting up, vehicles loading and unloading and so on, especially is suitable for open-air and the non-power source work.