Shure N91ED Stereo Elliptical Stylus * Possibly NOS * See Video

The Shure N91ED is a high-trackability elliptical stylus designed for the M91ED cartridge, featuring a diamond tip bonded to a low-mass cantilever. It is known for its excellent tracking, typically requiring a light tracking force of 0.75–1.5 grams (1.25g nominal). 

Key Specifications:
Stylus Type: Elliptical diamond 
Tracking Force: 0.75 - 1.5 grams.
Color: Usually yellow or black.
Compliance: High (approx. 25 cu).
Compatibility: Designed for Shure M91ED, M91E, and M93E cartridges.