The wrench 4mm and 5mm guitar neck tension rod with end balls is elongated, ideal for narrow or deep truss rods such as guitar adjustment. Gauge: 1.5mm, 2.0mm, 2.5mm, 3.0mm, 4.0mm, 5.0mm, 1/20in, 1/8in, 3/16in. The guitar hex key set is made of carbon steel, durable and highly wear-resistant. Various gauges suitable for most guitar screw adjustments. For locking hex screws, adjusting the guitar neck. The 6.35MM (1/4 inch) model pipe wrench is suitable for most folk guitar series, (not suitable for classic guitars of this brand)The 7MM model pipe wrench is suitable for some Korean and guitars. According to the actual size of your piano, the 8MM (5/16 inch) model pipe wrench is suitable for some American electric guitars and electric guitars, e.g. Color: BlackMaterial: MetalPackage Contents: 1 x 4mm Ball Wrench, 1 x 5mm Ball Wrench, 9 x Wrench Set3 x Pipe WrenchOnly the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture to be slightly different from the real thing. The allowed measurement error is +/- 1-3cm.