The General Pump Y60025920 is a new seat for unloaders. It replaces a worn, damaged, or leaky seat. Stainless steel construction provides superior corrosion resistance. Seat measures 8mm and the O-ring size measures 1.78mm. Fits unloader models PULSARZ, PULSAR4HPSM, PULSAR4KHPEZ, YVRP15W, YVB75KDMN21, and YVB75KTPF21. A genuine OEM General Pump part. Ensures a proper fit when installed in the recommended models.