UN can be used both for piston and rod seals. This packing has large section and can be used for wide range of operations.

USH can be used for both piston and rod seal. This packing has small section and can be fitted in integrated groove.

1) Aftermarket Hydraulic Seal - UN 18x26x5 PU ( 18 x 26 x 5 ) - TAIWAN
2) Aftermarket Hydraulic Seal - USH 18x26x5 NBR ( 18 x 26 x 5 ) - TAIWAN
3) NOK Hydraulic Seal - USH 18x26x5 NBR ( 18 x 26 x 5 ) - NOK (ORIGINAL JAPAN)

Inside Diameter = 18mm
Outside Diameter = 26mm
Width = 5mm