The H85-255/80 barretter from STV was later re-named the 85-255V0.08A when STV became part of Telefunken. This iron wire and hydrogen filled current stabiliser will maintain an 80 mA current for changes in HT from 85 to 255 volts.
The STV logo with the Stabilovolt trade mark. The Type designation is below.
The coiled iron wire.
Another example minus the base cap.
The exhibit came in original wrapping. A corrugated card roll with an outer paper layer. The wrap was sealed with this label - recreated here from several images so as not to damage the packaging.
The wide glass tube envelope is 40 mm in diameter, and excluding the B4 base pins is 168 mm tall.
References: Data-sheet, 1040 & 1043. Type H85-255/80 was first introduced in 1939.