SAEC SAG-052

Arm height and stylus rake angle are audible adjustments, and they are also the ones people guess at. The SAG-052 removes the guessing for WE-709 and WE-712 owners.
It is a precision acrylic gauge that sits on the record surface. You adjust arm height until the horizontal line engraved on the gauge runs parallel with the top surface of the headshell. That gives you a true horizontal arm at actual playing height, which is where it matters, not at rest. It works with any flat topped headshell, including SAEC's own SHS-5.
The second job it does is overhang checking. A vertical line is marked at exactly 52mm, so you can confirm the distance from the headshell mounting face to the stylus tip at a glance. That 52mm figure is the standard mounting dimension for SAEC headshell geometry.