The 80 Grit TR25 (photo shown is 150 Grit) is a rounded taper shaped diamond bur. The approximate head diameter is 3mm at the tip and 5mm at the base, and the approximate head length is 9mm. This bur is great for grinding or carving all types of stone, glass, tile, metal, wood and more... The 80 Grit is intended to be used for bulk removal and rough cutting. As with all Lasco Diamond Burs, the 80 Grit TR25 is a high quality, durable, 100% Natural Diamond bur, and is made in the USA. The TR25 is also available in 40 Grit, 80 Grit, 150 Grit, 200 Grit, 400 Grit, and 600 Grit.