Lang Tools 4651 Automatic Slack Adjuster Release Tool and Wrench Made in the USA, Lang Tools (4651) Automatic Slack Adjuster Release Tool and Wrench is for use with automatic slack adjusters on Meritor systems. The 4651 includes a fork-end tool, which is for releasing the tensioner button, and the 5/16" double square offset reversible wrench features an E-Z Grip handle. For adjusting automatic slack adjusters on Meritor systems Release the anti-reverse mechanism without prying and apply more turning power with less fatigue to the hand Made in the USA