Virtual Hagelin M-209

A 3D simulation of the Hagelin M-209 cipher machine

In cryptography, the M-209, designated CSP-1500 by the Navy (C-48 by the manufacturer) is a portable, mechanical cipher machine used by the US military primarily in World War II, though it remained in active use through the Korean War.

The M-209 was designed by Swedish cryptographer Boris Hagelin and manufactured by Smith & Corona in Syracuse (New York, USA). It was based on the C-38 which itself was an improvement of an earlier machine, the C-36.