KH-203-9-B-.750 Apex Universal Extension Wrench allow you to operate in hard to reach places. Apex impact universal socket extension wrenches are manufactured to last in the most demanding environments.. KH-203-9-B-.750 Apex Universal Extension Wrench is recognized as the industry leader in impact universal extension wrench tooling throughout the aviation industry as well as automotive, heavy industry or anywhere quality tooling products are required. Apex impact universal socket extension wrenches are not designed to be used with impact drivers.