The MTX is a Thunder 6000 series, the one in the pic looks like a 10 so that makes it a 6104 assuming its 4 ohm. MTX had 2 versions of both the 6000 and 8000 series, one has a gray plastic cone and the other is an aluminized (shiny chrome looking) plastic cone. The non aluminized models were the first ones and the aluminized ones are the newest. The way to distinguish the 6000 and 8000 series is by the stiffening ribs on the cone, the 6000 has 8 stiffening ribs, the 8000s have 12 stiffening ribs and they also have 12 mounting holes for the screws, regardless of basket size. The aluminized cone version is denoted with an "a" after the model # - ex 6124a for a Thunder 6000 12 in svc 4 ohm. The voice coils on the 6000s are 2inch but they will handle more than the rated 250wrms. The 8000s have a 2.5in coil 4 layer coil, the 15 version is an 8 layer coil.
I know this because I have owned 6000 10s and 12s and 8000 10s and I'm currently running an 8000 15. I have used many MTX subs, so I know a crap ton about them.