Flat Lensboard with 39mm Hole & Rear Recess for Beseler 23C and 4x5 Enlargers - Used

4"x 4" flat metal lensboard with 39mm hole and "pilot light" for mounting enlarging lenses with 39mm mounting thread on Beseler 23C and 4x5 enlargers. The lensboards have a counterbore on the rear, and are typically used for 63mm - 105mm lenses. The lensboards are not threaded - a 39mm retaining ring (jam nut) is required to mount the lens. These lens boards are used and may have cosmetic marks from previous use, but are in perfect working condition.

Note: The "pilot light" is intended to cast a small amount of red light on the aperture scale of the enlarging lens. This may be helpful when using lenses that do not themselves have an illuminated aperture scale feature. However, if the light is not required or wanted, it's easy to block the light by placing a small piece of black tape over the light pipe on the rear of the lensboard.