The 202STH is an indirectly heated triode hexode frequency changer (mixer) designed for universal sets without a mains transformer. The 200 mA heater is designed for series connection as part of a heater chain.
The BVA Guarantee contained in boxes of members of the BVA.
This image shows the boxes used in the late 1930s. Note the purchase tax and the price on the carton. This was a time of resale price maintenance where the maker set the selling price for all retailers.
Thanks to Alan Stepney for the images.
The classic envelope is 44 mm in diameter, and excluding the B7 base pins is 109 mm tall.
References: 1043. Type 202STH was first introduced in 1937.