Atari Ultra Pong question

[BassGuitari]

I've been researching the different Atari Pong systems recently and noticed that in every photo I've seen of an Ultra Pong Doubles, the badge on the console only says "Ultra Pong." Also, the model number on the bottom stick reads C-402, but makes no indication of (S) [ultra Pong] or (D) [Doubles]. So are Ultra Pong and Ultra Pong Doubles the same system? It appears like they simply came in different boxes and Doubles came with an extra set of paddles. Even the manual was a onesie for both systems, the title reading like something to the effect of "Ultra Pong and Ultra Pong Doubles."