It takes screw in phase plates and has a 40x fitted. There are 6 positions
marked A to D and O. There is a hex key adjustment and centring screws. The
centring screws adjust a round plate at the bottom of the unit and there is a
5.7mms thick ring followed by a dovetail above that. The centrable ring is 3mms
thick. The hex keys seem to be used to centre the phase plates to the condenser.
That assumes that the dovetail fits in something that allows the ring to centre
in the normal way.

I bought it intending to adapt it to another make of scope but it's just sitting
there and I have something more suitable. Condition wise I would say near mint.
One scratch on the top of the unit and a marks on one side of the dovetail which
may well clean off. It also has an iris and is very solidly made. I reckon it
owes me ukŁ35 (us$56 at paypal exchange rates). If anyone is interested I'll
post photo's.

John