Hex truss rod wrenches: For 5/16" (Gibson), 9/32" and 1/4" hex nuts.
Allen truss rod wrenches: For 1/8", 4mm and 5mm Allen nuts.
Soundhole truss rod wrenches: Right-angle tools for easily adjusting an acoustic guitar neck through the soundhole. 1/8" wrench reaches 5-1/2" (13.97cm) inside the guitar. 5mm wrench has 2" (5.08cm) reach, and works for Martin guitars made before August 2007 that have a soundhole-accessible truss rod.
Truss rod wrench for Fender: The 3/8"-wide (9.52mm) flat blade has the right taper and size to adjust a traditional Fender truss rod efficiently, without marring the nut.
Gripper truss rod wrench: This special tool lets you adjust a worn 1/8" Allen nut. 3/8" (9.52mm) taper from .121" to .135" (3.07mm to 3.43mm), giving you a snug fit to turn the nut and avoid a costly replacement job.
Pocket truss rod wrenches: Compact tools with a 1-1/8" (28.58mm) "bullet" socket that fits into a recessed truss rod access cavity. For 5/16" (Gibson), 9/32" and 1/4" hex nuts.