8T-1788 is a Caterpillar piston seal (Seal Type 3) used in Cat hydraulic cylinders. Catalog entries list 8T-1788 with dimensions: A 0.63 in (15.98 mm) and B 5.34 in (135.76 mm). Cross references include 9J5558, 8C3824, and 8C3825, reflecting its role as a piston-seal assembly for Caterpillar equipment. This part is documented in Cat official catalogs and various aftermarket listings as a general-use Caterpillar hydraulic-seal component.
