The 6AL5 is a double signal diode and equivalent to the EB91.
These double diodes were designed for sound and vision detection in 405 line televisions. Additionally they are recommended for limiting and DC restoration, again part of a TV receiver functionality.
The two small diodes are separated by a central screening plate.
One diode showing the stitched anode and small central space for the cathode tube.
The thin glass tube envelope is 18 mm in diameter and, excluding the B7G base pins, is 37 mm tall.
References: Data-sheet & 1040. Type 6AL5 was first introduced in 1945. See also1945 adverts.
