For sale, a high-precision arc protractor for cartridge alignment. This protractor is made of 3mm high-quality acrylic, coated with a yellow film, and high-precision laser-cut and engraved. The first picture is for reference only; the real protractor looks like the one in the second and third pictures.
The arc protractor is the most accurate protractors for cartridge alignment; this one is designed for the SME 3012R and M2-12 tonearms.
 
The geometric features are compliant with SME specifications; see the first picture.
It is supplied with detailed instructions.
We also make custom protractors to the client's specifications.