The Sup 'R' Mod II is an RF modulator which was sold by M&R Enterprises in the late 1970s and early 1980s.
Apple made an arrangement with a small nearby company, M&R Enterprises, to manufacture and sell the devices.
[2] Marty Spergel, who ran M&R Enterprises, was told by Steve Jobs that it might sell up to 50 units a month.
[4] The Sup 'R' Mod II kit has a small printed circuit board, an antenna switch, and a coaxial cable with a ferrite core and RCA connectors.
Composite video is received by the circuit board through a short cable terminating in a Molex connector, which plugs into a header on the Apple II motherboard.