I just bought a used 23CII XL condenser enlarger and was trying to determine what bulb it takes. From my research it seems that some use a 111a and some a 140 bulb. If I'm not mistaken the heads that have the bulb coming out from the back of the enlarger and are parallel to the negative use the 111a. I just wanted to make sure this was correct before I purchased several of them at $8 a pop. I ordered a manual for it wont be here for a few days and I wanted to try and track down a bulb so I could use it for the weekend. Thanks.
Dan

There is a plate on the lower left below the head that specifies the bulb. Hope this helps. Mine says PH111a

Jon

Guess I should've looked a little harder huh? I just picked it up this afternoon and didn't notice the plate. Mines also 111a. Thanks Jon.

This might save you $1.01 per bulb. Not sure how much shipping will set you back.
http://www.replacementlightbulbs.com/lampph111a.html
Best regards,
James