Durable all purpose truck for any type of skateboarding. 55mm tall for optimal performance and wheel clearance with wheels 56mm and under. A356 T6 Aluminum Hanger & Baseplate The best lightweight aluminum alloy heat treated to T6 condition for strength, durability, and grind feel. SCM435 Chromoly Steel Axle Highest quality and durability available. Grade 8 Kingpin Never break, never bend. 159 and 169 models feature 6 hole universal baseplate with old and new school mounting pattern. Independent Trucks are Built to Grind and Guaranteed for Life.