non-interchangeable screw-threaded connector
1History of the single-lens reflex camera — The history of the single lens reflex camera predates the invention of photography in 1826/27 by one and a half centuries with the use of a reflex mirror in a camera obscura first described in 1676. Such SLR devices were popular as drawing aids… …
2Gender of connectors and fasteners — A male threaded pipe, left, and female threaded elbow. In electrical and mechanical trades and manufacturing, each half of a pair of mating connectors or fasteners is conventionally assigned the designation male or female. The female connector is …
