Bearing Buddy, 1781SS - Bearing Buddy
The axle hub is filled with grease until the grease forces the Bearing Buddy® piston outward about 1/8 inch.
Because the piston is spring loaded, the piston exerts a slight (3 psi) pressure against the grease, which maintains a slight pressure between the inside of the hub and the outside environment.
When the hub is submerged, water cannot enter the hub because of this pressure. Sold in pairs