Audio-Technica AT-CAP1 Cartridge Alignment Protractor

This protractor uses the Baerwald alignment method to set a phono cartridge’s offset angle and null points. Cartridge alignment is critical for optimal playback, ensuring that the stylus tip remains as tangent to the record groove as possible as it travels across the record. 

Typically, if your tonearm’s effective length (the distance from the tonearm pivot to the stylus tip) falls between 222 mm (8.7") and 250 mm (9.8"), you can use the Baerwald method to align the cartridge.