The Milwaukee M18 FUEL ONE-KEY impact wrench kit is easy to use. To ensure proper compatibility, be sure to verify the proper drive size. This impact wrench kit has a 1 in drive. This impact wrench kit is made of aluminum with a finish. The overall length measures 17.94 in. Most of the part numbers in this category have a maximum RPM. The maximum RPM is designated for both safety and as the upper limit for performance. In this case the maximum RPM is 1200. The device is m18 redlithium battery powered. Weighs only 24 lb for convenience and ease of use. Packaged 1 kit per case.