UCON™ LB-550-XY26 is a specialty rust-preventative fluid that can be compounded with selected rust and oxidation inhibitors. This fluid can then be used as a lubricant to coat the surface of equipment such as hydraulic brake parts and other similar machinery before and during assembly. This rust-preventative fluid is compatible with DOT 3 brake fluids but not silicone-based fluids. It can be mixed with natural oils, plasticizers, organic solvents, resins, and gums.

UCON™ LB-550-XY26 is a polypropylene glycol monobutyl ether fluid with a wide viscosity range, giving it phenomenal load-carrying capacities. This fluid does not have any adverse effects on braking system elastomers and is able to provide lubrication to brake parts during assembly. UCON™ LB-550-XY26 is a rust-preventive fluid used to coat metal parts with a kinematic viscosity of 114–145 cSt at 100°F.