Jiayouy 4Pcs Luthier Tools Set Dual Scale Guitar Neck Notched Straight Edge String Action Gauge Ruler Fret Rocker Fret Leveling Beam for Guitar and Designs of Distinction At the base of its Color:Marble Parkour At the base of its heavy duty steel frame are 4 casters for smooth rolling mobility (with 2 that lock) and effortless work stand mobility storage for project versatility and convenience Guitar maintain and repair set: you will get 1 piece guitar neck notched string measurement ruler 1 piece 1 piece string action ruler 1 piece fret Leveling Tool and 1 fret rocker string height gauge Step 2 Adjust the neck to a flat position