Every ounce counts, eliminating a crank spider, chainring bolts as well as front derailleur or chain keeper can shave precious grams. North Shore Billet uses aerospace quality materials including 7075 T6 aluminum machined in house in Whistler, British Columbia to produce high quality parts. Using a variable tooth thickness does not allow the chain to wobble or move back and forth resulting in next to zero chain drops, so forget your chain keeper and direct mount your Variable Tooth Chainring.