It consists of main parts, sling, capstan, and protection chains.
- Be made of durable super light aluminum alloy, adjustable legs, safety factor more than 10. There are protection chains at the bottom. 
- Automatic lock capstan for rising and falling, to protect sling work. 
- The cable of sling is made of stainless steel, good tenacity and rust proof.  
- Convenient combination is suitable to fix at the well and pit mouth. Out of the limit of the ground unevenness.