LINCOLN INDUSTRIAL 1/8 NPT Heavy-Duty Hydraulic Coupler Grease Fitting Steel The LINCOLN INDUSTRIAL LNI-5845 is a heavy-duty hydraulic coupler designed for use with grease guns in various automotive, agricultural, construction, and industrial applications. This coupler ensures a secure and leak-free connection to hydraulic-type grease fittings, providing efficient lubrication for heavy equipment and machinery. Its robust construction and high-pressure rating make it a reliable choice for demanding environments.