The Alpha is currently divided into 4 variants. Each one has an alpha-numeric designation so you can tell them apart.
The first two letters tell you what type of LED the light uses. RIght now that could be an MCE, XML, XPG, or XRE.
The next two numbers tell you what type of battery. Currently all lights use 18650 size batteries. If I ever make a light that uses AA batteries then the designtation might be something like MCAA-B.
The letter after the dash indicates the type of lens or optic used. Right now all Alpha lights use the Ledil BoomSS reflector, hence the designation -B.
I do have a very limited number of TIR (Total Internal Reflection) optics available for XML based lights. Contact me if you are interested. The TIR optic produces a more intense hotspot and correspondingly less spill.