An SVG format of my previous file, Teletherapy Capsule.jpg.  A diagram of a typical teletherapy radiation capsule comprised of the following:
an international standard source holder (usually lead),a retaining ring, anda teletherapy "source" composed oftwo nested stainless steel canisters welded to twostainless steel lids surrounding aninternal shield (usually uranium metal or a tungsten alloy) that protects acylinder of radioactive source material, often but not always cobalt-60. The diameter of the "source" is 30mm.