I installed a pair of bearing buddies on my boat trailer. When I attempted to fill the bearing using a grease gun, the grease fitting broke off and grease poured out down my wheel and onto the concrete driveway. What a mess! Since an auto parts store was closer than Sportsmans, I elected to buy some real metal grease fittings rather than the cheap aluminum ones on the Bearing Buddies I bought, and replaced them, then reinstalled the Buddies on my axle. Using stainless steel is nice, but if you use aluminum fittings on the working parts, you invalidate the real value of what could be a good product.