This Galvanized 6 Lug Spare Tire Mount bolts directly to your I-beam trailer, allowing you to easily and conveniently store a spare tire and wheel for your boat trailer! The 4 hole mounting plate allows you to easily drill and bolt the mount directly into your trailer's I-beam and safely hold your spare 5200-6000 pound hub and tire assembly securely and away from the road and any hazards. This spare tire mount has a galvanized coating, which protects against corrosion and the elements, making it perfect for boat trailers that see heavy freshwater or saltwater marine use. The #42 spindle is the standard spindle size for 6 bolt trailer hubs, so select a Galvanized 6 Lug 5200-6000 lb Idler Hub if you need a spare hub to complete your project.Features:- #42 Spindle fits 1 1/4" Outer Bearing x 1 3/4" Inner Bearing with 2 1/4" Seal Surface- Corrosive Resistant Galvanized Steel Coating- I-Beam Mount Style Spare Tire Carrier- Fits Most Standard 6 Lug Trailer Hubs- Includes spindle washer and castle nut