This is a Mazda version of the ECC83 and was made in the UK. The ECC83 high impedance amplifier triode was designed specifically for audio use and has a high amplification factor of 100, primarily intended for use as a resistance-coupled amplifier or phase inverter.
Made in England. The two triodes are mounted side by side without a central screen.
This looks like one anode but in fact the anode is folded and stitched on one side. The right hand stitch is from the other anode. Most ECC83s have two piece anodes stitched together, the other ECC83 we have with this anode construction was made in East Germany.
The thin glass tube envelope is 20 mm in diameter and, excluding the B9A base pins, is 48 mm tall.
References: Datasheet, 3002 & 1040. Type ECC83 was first introduced in 1954.