Quarter Turk, the name of this series, refers to the top surface of the cymbal.
The raw surface is referred to as "Turk" and "Quarter" is related to the extent to which this raw surface has been lathed down. This is the reason for the grooved surface, which you will only find on the top surface and not on the underside of the cymbal.
This 20" Quarter Turk ride in particular has a nice dry (but not super dry) sound, which also helps defining the cymbal's very fine stick attack.
A very nice all-round ride that does not stick out too much to any particular side while still retaining its personal character.
A cymbal you can use for pretty much anything, and which also likes to function as a crash cymbal - should you need it.