Rider Weight Limit: 100 lbs. Precision machined from 7075 aluminium. Replaceable redesigned spider for use w/ standard 110mm BCD chainrings, or remove the spider for use w/ Alumilite SX Sprockets. SX Mini cranks have the highest strength-to-weight ratio of any mini crank on the market. SX Mini cranks are compatible w/ any standard square taper spindle. Lengths: 125, 135mm to 170mm in 5mm increments. Made in the USA.