Gripper Truss Rod Wrenches Dang! Somebody used the wrong size wrench, and now you can't adjust that worn Allen truss rod nut. Fear not, our Gripper wrenches can save the day! Each wrench has a 3/8"-long end that tapers from slightly undersize to slightly oversize, giving you a snug fit to turn the nut and avoid a costly replacement job. Our veteran guitar technicians developed these high quality steel truss rod wrenches. The length, comfortable rubberized handles, durability and variety of sizes let you perform formerly difficult truss rod adjustments with ease. The straight wrenches are 12-1/2" long, keeping your knuckles safely away from the peghead. #6210-G Gripper wrench has a special angled handle for tuner clearance on 6-in-line pegheads. For 1/8" Allen nut; 2" reach. Special notes for the soundhole wrenches 4mm is for Hot Rod truss rods. #6110-G is for pre-August 2007 (compatible) Martins; #6114-G and #6212-G are for later Martins. Triple-bend wrenches provide clearance under the guitar's braces.