A Little Gem ! Marconi (?) Model "G.B.1091"

A very high quality small morse key marked "G.B.1091". Terminal screws are 3BA and the cover is a cast alloy. Small parts are nickel plated brass, and the main frame and lever may be cast alloy. The 4 base mounting screws & nuts are of a similar diameter to 3BA, but not 3BA. (finer thread - could be 1/8" BSF) Contacts are quite large at 3/16" Dia.

Marconi style knob is 7/8" in Dia. and about 5/16" thick (22mm x 7mm). Interestingly the larger Marconi Type 100 key has the same design knob measuring 1&1/8" Dia and 5/16" thick (28mm x 7mm). Weight of key with wood base 220g ( 7 & 3/4 oz). The wooden base measures 3 & 7/8" by 2 & 1/8" (99mm by 54mm) The key's black base is 2 & 3/4" by 1 & 5/8" (70mm by 41mm). The overall length of the key is 4 & 1/4" (108mm). Pretty sure this is a MARCONI UK key.

A key of extremely high quality and very tactile.