Sturdy steel construction Compatible with hollow crank axles including Shimano Hollowtech II, FSA, Sram, and RacefaceThree position height adjustment for use with 26, 27.5 and 29` bikesFolds for easy storage and transportationHollow CranksSteelBlackRaceface CompatibleSPN-20UPC/EAN/GTIN: 4944924423216