Hot Dipped Galvanized Hub, great for Boat trailers! This Trailer Hub is works for trailers with straight spindles that accommodate 1 1/16 inch diameter bearings. Common trailer tire sizes for this capacity trailer hub are 8 inch - 13 inch. Fits 2000-2500 lb. Axles Includes hubs, bearings, and seal Outer Bearing Number 44649 1 1/16 inch inner diameter Inner Bearing Number 44649 1 1/16 inch inner diameter Rear Seal Dimensions: The Grease seals included in this kit are a 1 1/4" Inner Diameter Seal and a 1 1/2" Inner Diameter Grease Seal. You will only use one of these Sizes on your Axles Spindle. We include both for customer convenience, as sometimes it is very difficult to know which is needed. On the Axles we sell, they use the 1 1/2 Grease Seal. Test Fit both on your trailers spindle, and discard the one that will not fit. Only one Grease seal is used per hub. Rated to 1250 lbs eachIf youve ever experienced difficulty installing dust caps, check out this 1.98 Trailer Dust Cap installation Tool for much easier installation