Champion ZM1393 High Pressure Piston With Pin is a replacement piston kit for Champion R-Series air compressors, including the R70A pump model. The kit includes a high‑pressure piston, a piston pin, and a retaining ring, enabling proper piston assembly and secure wrist‑pin retention during high‑pressure operation. It is compatible with Grainger part numbers 1WD25, 1WD91, 1WD92, 1WD93, 1WD94, 1WD95, and 1WD96, and is listed as compatible with Champion pump variants PL40, PL70, R40, and R70. Marketed as an OEM Champion replacement part for R-Series pumps, ZM1393 is designed to support rebuilds and service of Champion R70A configurations.
