KVADRO - Ceramic Nail Bit - Cone, Red - F #409

A white ceramic bit with a tapered head and a rounded tip, set on a metal neck with a red ring. The ring and the tube cap are red, which marks grit F in the KVADRO ceramic bit color code: the soft grit, one step above the softest yellow XF. Size Chart Part Size Head diameter 0.6 cm (0.23 in) Head height 1.3 cm (0.51 in) Total length 5 cm (1.96 in) Shank diameter 0.235 cm (0.092 in) Weight 7 g (0.24 oz) Tube 7 x 1.3 cm (2.75 x 0.51 in) Details Product: Ceramic Nail Bit, model #409 Shape: Cone Grit: F, red ring and red tube cap Head: white ceramic with a diagonal crosshatch of cuts Packaging: clear plastic tube with a red cap Questions What does the red ring mean? Red marks grit F, the soft grit in the KVADRO ceramic bit color code. How do I tell it from the other grits? By color: yellow is XF, red is F, blue is M, green is C and black is XC. The tube cap matches the ring. What is the shank diameter? The size photo shows 0.235 cm (0.092 in).