An American Ebonite aid with a metallic diaphragm first patented in 1895 by James Maloney.
It is engraved on top of the ear piece ‘Globe Phone MFG Co Boston’ and this company was in business from 1907 through the 1920s. The device is unusual in featuring a diaphragm and also because the earpiece fits over the ear and is held in the hand. Complete with its original black silk strap. Ebonite is a registered name for a hard rubber.