Definitely not a Kahler flat mount. I replaced the whammy on mine with a Kahler for most of the time I owned it. A Kahler has an axle that rolls the strings back over fixed rollers. This is really a very fancy knife-edge trem with self contained internal springs. There is no back cavity like a Strat or Floyd style bridge. Just a massive front rout.
Current:
GTH-1
Completed:
AST-1FB
First Act ME276 (resurrected curb-side find)
ES-5V
Scratchie lapsteel
Custom ST-1 12 String
JBA-4
TL-1TB
Scratch Lapsteel
Meinl DIY Cajon
Cigar Box lap steel
Wishing:
Baritone
Open D/Standard Double 6 twin neck