Features and Benefits: Designed to fit the slotted adjusting screw in tapered kingpins; Application: Most Mack front axles (12,000 to 20,000 lbs.); Visit ctatools.com for application details; Use with a 1/2" square drive ratchet or breaker bar; Application: Most Mack front axles (12,000 to 20,000 lbs.). Visit ctatools.com for application details. Use with a 1/2" square drive ratchet or breaker bar.