Offered is a very interesting, unused, Kayden Fully Automatic Insulin Injector complete with the original display case and packaging materials.
The chrome plated injector is in mint condition and resides inside its plastic case. The patent #2295849 dates this unusual tool of the trade to 1942. Measuring 4.75" long, the injector barrel displays the imprinted patent date and other info (see photo).
The injector was an alternative device that was employed by those patients who preferred not to use the typical needle and syringe. As a precision instrument, the user was able to adjust the depth of injection, and then the device, once user-activated, injected the insulin. Voila!
Not sure of the level of popularity this device held, but this is the only one I have seen.