#811528 Cat Pumps Unloader Repair Piston Assembly 3DNX25GSI & 3DNX27GSI – OEM
#811528 Unloader Repair Piston Assembly Kit 3DNX25GSI And 3DNX27GSI Pumps.Refer To Service Manual For Service Procedure. See link with parts breakdown.https://www.catpumps.com/sites/default/files/products/pdfs/3DNX25GSI_C.pdf