50mm x 21mm Enlarger Lens Adapter for the Beseler 3-Lens Turret

The Beseler 3-lens turret is designed to accept lenses with 39mm "Leica" mounting thread. This means that some longer focal length lenses with 50mm mounting thread, such as the Rodagon 150mm, Componon-S 135mm, and Componon-S 150mm, cannot be mounted directly on the turret. This 50mm to 39mm adapter ring allows mounting of those lenses on the turret. Simply screw the lens into the adapter, and screw the adapter onto the turret.

This adapter can also be used in other applications where a 50mm to 39mm "Leica" thread adapter is required.