Assertion: headphone's design | /r/CreatedBy | western electric
Facets:
value: for use in ww-i
type: PURPOSE
Source sentences:
text: They were based on the same design made by Western Electric for use in WW-I which include the model P-II used with the Signal Corps DeForest BC-14A crystal radio, and the model 194-W used in the WW-I leather pilot flying helmets.