From KBH the

"The Chromega B Dichroic covers formats up to 2"x2" and was initially fitted to the B-22, then the B-66 and B600 enlargers."

"The Chromega B Dichroic is quite suitable for standard column length enlargers, but we'd prefer one of the later C700 or C760 colorheads for XL models. Since the Chromega B requires an external power supply,"

Take a look at their site, you might be able to figure out the model. It sounds like the C760 Lamphouse would fit depending on the bracket.
Here's a snip from the manual: