Application: for marble only. 
Connection: 1/2" shank or other size shank sizes 
Advantage: fast cutting, minimizes chipping, long life.

Electroplated anchor bit 
Application: granite, marble. 
Arbor: 3/8" or 1/4" shank,  M14 thread. 
Fast cutting action, vacuum brazed for long life. 
Can be made according to drawings and samples.