Original German Pre-WWII Brass Optical Tripod Mounting Coupler and Calibration Unit MG 42 Bolt & Barrel Assembly The bore is clear with

The bore is clear with good rifling

This example however is quite different

Seen before in photographs this is the first time we've seen these "in the flesh"

It was also originally intended only to accept the Brown Bess socket bayonet secured on the foresight block

We were hit by flak about three minutes before bombs away

Original German Pre-WWII Brass Optical Tripod Mounting Coupler and Calibration Unit MG 42 Bolt & Barrel Assembly The bore is clear withOriginal Item: Only One Available. So often these are missing, the interfacing unit allowing a "Rabbit Ears" pair of Binoculars Field Glasses to be mounted onto the standard German Optic's tripod. The early production example is constructed almost entirely of BRASS, which has been polished, and dates from the late pre war 1930's. Brass became a very scarce commodity once WWII started, so these couplers were then constructed from steel. Original