It's a Sonicor 52 (Either that or a 32, can't remember off the top of my head). Picked it up for $20 on TM as it "didn't work properly"
Adjusted the tuning bar, replaced the missing locking screw and all is good (the cat doesn't think so though)
The bath on this one is about 15cmx15cmx10cm deep which is just about right.
Love watching big gobby flakes of crud just fall off stuff, not so nice coming back to a steaming water and a coin that looks like it's been sandblasted though.