According to the Odyssey website, The G-Sport Ribcage rim has been one of the only rims to have true design breakthroughs in the last few years. The spoke holes are drilled and re-enforced with ribs for cross-spoke lacing, where the spokes goes from one side of the hub to the opposite side of the rim for increased strength. The cross-spoke created more of a web of structure, which multiplies the stiffness and strength. This has been adopted by a few other companies but never done as well. The outer walls are extra thick to protect against case dents, while the other walls are extra thin to keep it light. However you put it the G-Sport Ribcage is one of the strongest most reliable rims on the market with an awesome strength to weight ratio. Sizes: 20"" Only Drillings: 36. Weight (Hard Anodised): 500g /17.6oz Weight (Chrome Plate): 540g / 19oz Width: 36mm ERD: 389mm