The GRACO D05080 is a check ball kit designed for use in GRACO pumps, specifically for 1/2-inch and 3/4-inch models. The kit contains check balls made from FKM (Viton), a high-performance fluoroelastomer known for its chemical resistance and durability. This kit is intended for maintenance and repair of GRACO pump check valves, ensuring reliable sealing and fluid control within the pump assembly.