Magnavox were/are one of the US' bigger TV manufacturers in the latter part of the 20th century, and it's down to 1 man - VP of Marketing in 1968 Gerry Martin - that they became responsible for launching the TV game industry in 1972, funnily enough the month before Nolan Bushnell founded Atari! Remember them? :)

Ralph Baer (then of Sanders Associates) had been toying with TV games since the early 1950s, the most important of which was built in 1968 and was called the Brown Box since it was, er, brown. Problem was, everywhere TV company he took it to wasn't that interested. Once Gerry Martin convinced the Magnavox board to go with this TV game, the rest quickly became history!

Several pong consoles were eventually produced, from the original (renamed the Odyssey) through the 'tennis' pong range of the mid-70s to the cartridge machines in the late 70s and early 80s, the latter few licensed by Philips in Europe, such as the G7000 (rebadged Odyssey 2) and the G7400 (ony released in Europe)

No point in me reinventing the wheel here - everything's covered in excellent detail over at David Winter's Pong Story.

Odyssey :o)). The world's first TV game, boxed complete with all accessories and overlays!
Baseball. Boxed complete with screen overlay, team cards, 'calculator' card and instructions.
Odyssey 300 (1976), boxed in mint condition, though I dunno if there should be an instruction booklet or not.
Philips G7000 console, aka Magnavox Odyssey 2 complete with controllers and PSU. 1978!
Boxed carts for the G7000.