Hi Chris,
This is the one you are thinking of.

I believe the measurements are 6.5 x 2.5 x 3(tall).
It was made for ackies, but I moved them out of there and into a trough eight months or so ago. Overall the only real problem I have with it is it does not allow deep enough dirt, I tried all sorts of barriers to hold dirt above the windows, but in the end I gave up for a trough with ackies. If it had a deeper 'pan' ( it is somewhere around 8-10" ), it would probably work OK. I have done some work with making the heat lamp placement flexible, and have used this enclosure for raising argus, goulds, and currently peachies. I kind of like rotating what is in here, because I get to see them more often than if they are in the garage. Although it was disconcerting to be watched by tripoding argus while eating dinner.
If there is anything else I can help with, just ask.
Good Luck,
--Robert