Used from day one on through now. Also used by many Spyder clones.
On the left.
Includes all Spyder/Raven markers but the EM1, Primal, VS series. I have read that the MR2/3 also has a different mounting style.
Only frame that will fit this body without MAJOR work. Not only being longer than a standard Eframe, the mounting holes are farther apart.
This is a view from the front of the marker but is that way all the way down.
EM1 / Primal
Similar to the Bushmaster tray but about ½” longer.
Unique to this marker line. No other frames are known to bolt on.
On the right.
Photos used from Otter's site, Spyderzone.net & personal photos