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 protractor for cartridge alignment; this one is designed for the following Graham tonearms:
 
1.5
1.5T
2.0
2.1
2.2
Phantom 
B44
Phantom II
Supreme
Robin
 
The geometric features are compliant with Graham specifications; see the first picture.
 
It is supplied with detailed instructions.
We also make custom protractors to the client's specifications.