A professional quality, heavy duty set of NINE impact extension bars. Manufactured from Chrome Vanadium Steel (CR-V) for longevity and durability and helps resist abrasion, oxidation and corrosion. Made using heat treated hardened HRC 43-45 steel for added strength. They come in a 1/4″, 3/8″ and 1/2″ drive and can be used with air tools and all kinds of impact tools. The sizes are as follows: 1/4″ Drive bars: 50mm (2″), 100mm (4″) and 150mm (6″). 3/8″ Drive bars: 45mm (1.75″), 75mm (3″) and 150mm (6″). 1/2″ Drive bars: 50mm (2″), 125mm (5″), 250mm (10″). Sizes are laser etched on the side for easy identification. Black oxide finish for corrosion resistance. Supplied in a plastic tray for neat storage and easy transportation.