Feature:1. 1.98in bearing buddies, keep pressure on the grease inside the bearing to prevent water and dust from entering.2. The springloaded piston exerts a slight pressure of 3psi on the grease, maintaining a slight pressure between the inside of the hub and the outside environment.3. An automatic pressure relief feature prevents overfilling and over pressurization, reliable to use.4. Help you avoid serious mechanical problems and provide longlasting and economical solutions for bearing protection.5. Simple to mount, it is quick and no mess in filling them up with grease gun; just remove the cap and you can monitor the grease level at any time.Specification:Item Type: Bearing BuddyMaterial: Stainless SteelApplication: Fits on most trailers boat with 1.98in hub diameter.Package List:2 x Bearing Buddy