This is a pair of Bosch 6" horns from the early-mid 1950s, part numbers 000 542 31 20 and 000 542 32 20, 290Hz and 345Hz. They were used on W187 models such as the 220 Cab A, as well as the W198 Gullwing, W188 300S (coupe, cabriolet and roadster) and W121 190SL.

They are in very good condition including the central Bosch badges, and are in fully working condition (yes, they're LOUD).