Original 1943 electrical trade vintage ad for STRUTHERS-DUNN, INC.  Main office and plant was located at 1321 Arch Street, Philadelphia, PA.

Manufacturers of Shock-Proof Relays.

Dunco Type 17AXX - A Shock-Proof Relay That's Really Shockproof.

Here's a relay on which the contacts won't operate unintentionally, the Struthers-Dunn Type 17AXX, especially designed for rough and tumble airplane use. It is small in size and light in weight. It meets and exceeds all specified requirements for this type of unit. 

Unbound from a 1943 electrical engineering magazine, this unique old one-page advertisement would display beautifully matted and framed. Nice graphics. World War 2 propaganda. A fabulous addition to your retro electrical library.