This Pro crankset is forged from aircraft grade 7075 aluminum and the RXL external bearing is perfect for any terrain on or off the track. RXL comes equipped with a stainless steal External Bottom Bracket and a Sugino Compressor Cap. The 5mm thick 7075 chain-ring fits 1/2 x 1/8 chains only. Designed and tested in CA and approved by elite riders around the globe. Great value. Pay No Tax & Ships Free..