ATB down-haul weight for Boom Trucks equipped with Greer® LMI systems. This downhaul weight features a quick-disconnect stainless steel hasp for fast and easy removal. Weight is designed to encompass the lifting cable and be attached by the included chain and shackle assembly to the crane's anti two-block (atb) switch. The weight provides downward pressure while activating the ATB switch. When the load block or headache ball makes contact the weight is lifted up and anti two-block protection system is activated. Suitable for any crane or boom truck with any counterweighted or spring loaded ATB switch. Accommodates a single part of wire rope (cable). Includes: (1) Cast Iron hinged split weight w/ stainless steel butterfly latch. (1) Chain Assembly - 5'8" (1) 1/4 Clevis (shackle) Shipping Weight: 12.2 LBS. - (Greer® Part Number - A251005) - Parts for Electronic Load Moment Indication (LMI), and Anti Two-Block (ATB/A2B) systems used on Cranes, Boom Trucks, and other Lifting Equipment.