1. Finish:Bright zinc plating. 2. Construction:Made of heavy duty gauge steel and heat treated for extra strength. 3. Rigid: Welded with heavy duty gauge steel for extra strength. 4. Axle:3/8"dia. bolt with lock nut for 3", 4" and 5"; 1/2"dia. bolt with lock nut for 6" and 8". 5. Fork Leg Spacing: 2".