22 mm scoring wheel for TR, TS and TF, Speed, Star and Fast Tile Cutters,High resistance to wear, Ball bearing mounted providing a soft scratch and a life of 300%, compared to SILVER scoring wheels, Titanium surface treatment extends life of this scoring wheel, Made of Tungsten carbide with a superficial Titanium treatment, Shaft made with a patented geometry for maximum precision and minimum vibration, Suitable for all surfaces for sharp scoring in hard ceramics with rough or structured surfaces. 22mm (7/8?) scoring wheel