Brown Aviation Tool offers its BAT-70 drill block. This tool allows you to drill perfectly straight holes on a variety of flat and curved surfaces. It features precision and hardened drill bushings for long life. Standard with the most popular aviation drill sizes of #40, #30, #21, and #10, the BAT-70 can also be customized with any size bushing desired. Completely manufactured in the USA. For more information visit www.browntool.com.