This listing is for single or multiple grinding tools, for the best deal we recommend to purchase the entire set, which is found as a separate listing. These are made to the same 1:10 taper specifications as all glass on glass tapered joints.
 
Sizes available are the 10/19mm,14/23mm and 19(18.8)/26mm are the fittings these grinders were modeled after.
 
They have been designed with maximum tool life in mind and will fit larger than the fittings preventing premature tool expiration due to grinding. How long the grinder lasts depends on how much material you have to grind. If the joint is formed precisely, you may get up to 300 joints made. If you have to move a lot of material, they’ll wear out pretty quickly.

These tools are named by what they are intended to grind, not what shape they are. It can be confusing. For example; The 14mm M tool is a stainless steel female grinding tool, and the 14mm F tool is a male shaped grinding tool.  These tools are made from high quality 303 stainless steel and are designed to be used in a cordless drill (Carefully!)

It’s recommended that you use Silicone Carbide (220 grit) to construct the joints. This may be purchased separately. You may also want a finer grade of Silicone for the final grind (also available separately) but most find the 220 may be all they need.