ocr: To Hoist Fuel Cell Shelf Service Module ( - - - - Y - - bo - - Service Module A Mold Line Counterweights Sling Bolt -Locking Screw, IA - - - - A - Rubber L Pad D - . 1 - - - - - Point of failure Chains permit adjustment Sling Adapter ot balance weights. Oxygen Shelf and Hoist Assembly