brand new and high quality Instructions: 1. Place this protractor on your turntable platter with hole over spindle. 2. Move cartridge/ tonearm until stylus rests exactly on center of bulls eye. (120.9mm radius). Check that cartridge is square with outer set of grid lines. - If not, loosen cartridge mounting screws and twist cartridge lightly until it is square. 3. Move cartridge/ tonearm until stylus rests exactly on center of inner bulls-eye (66.04mm radius), Rotate protractor around spindle as required. Check that cartridge is square with inner set of grid lines. - If not, change overhang, (move cartridge in or out along the axis) until cartridge is square. 4. Repeat step 2 and 3 till cartridge is square at both points. Tighten mounting, and recheck as above. Remove Protractor. Relax and enjoy! Features: High contrast cartridge alignment protractor provides improved visibility and eliminates tracking errors. Avoids the over-shoot distortion to keep high quality sound Link to turntable setup guide with instructions included, printed directly on the protractor. Works with an S -Shaped arm and any 1/2" mounted cartridge. for Extra magnifier make you more clear when adjusting the overhang. Calibration Protractor only, other accessories demo in the picture are not included! Specification: Material: Acrylic Type: Accessories Color: White Size: One Size Length: 18.9cm/ 7.44in Width: 4.0cm/ 1.57in Quantity: 1 Set Note: 1.No retail package. 2.Please allow 0-1cm error due to manual measurement. plz make sure you do not mind before you bid. 3.Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you! Package includes: 1 Pc x Overshoot Protractor 1 Pc x Magnifier