The Rhoads

Guitar String Ring in Black Tungsten. This guitar string ring features black tungsten with a phospher-bronze guitar string inlay.

Tungsten Carbide is the paragon of modern metal working. It is hard enough to cut steel, and its black exterior will never fade (it's around an 8 on Moh's hardness scale). We use jewelers grade tungsten carbide in every ring. 

Specs:
Band Width: 8 mm
Band Thickness: Circa 1.8 mm
Fit:

Materials: Tungsten Carbide, Guitar String