These flights offer the advantages of a pre-molded plastic flight with out the need for a proprietary shaft.
By maintaining the 90 degree angle they provide consistency in aerodynamic dart trajectory.  
The enclosed shaft slot prevents robin hooding and damage to the shaft. 
These flights will work with any nylon, poly or carbon fiber tradition 4 prong shaft. 

Aluminum or other metal shafts not recommended
 
350 micron thickness 
 
All flights sold in a set of 3