Lightweight 20" BMX race rims for Expert use.These lightweight, semi-aero box section alloy rims ensure a quick getaway out of the gate.Stainless nipple eyelets allow high tension spokes for a stiff wheel that transfers chain drive into forward motion with minimum effort.Available in 20x1 3/8" or 20x1.5"Recommended Spoke Tension:Front: 80 to 100Kgs.,Rear: 100 to 135Kgs..SpecificationsMaterial Niobium Alloy material with T-10 heat treatment.,Drillings 28, 32 or 36H,Eyelets Stainless Steel   ,Colour Black,Dimensions 24mm Wide,ERD 420mm (20x1 3/8), ERD 376mm  (20x1.5),ETRTO 451 (20x1 3/8), ETRTO 406 (20x1.5),Weight 388g (20x1 3/8").