The HXS-1 L-shaped hex wretches are selected in sizes especially useful to the bicycle mechanic. Ball drivers are included on the 2, 2.5, 3, 4, 5, and 6mm. The set also includes an 8 and 10mm. Park's special "speed bearing" attachment (a spinning journal bearing) comes on the 3, 4, 5, 6 and 8mm sizes to facilitate quick installation and removal on long threaded bolts. Made from 8650 chrome vanadium tool steel in the USA.