YAY-OK (also known as YAY-OK 1 or Yay-OK, Yay Ok, Yay OK and Yay-Ok) is Wally and Gus's robot friend that helps them on their adventures through space. He is voiced by Lee Tockar On the version Hebrew Yuval Segal.
He has one wheel to move around on, a rectangular body, a screen for a head, an antenna on his head, a chest panel along with 10 buttons, and circles on each side of his head and lines under his eyes. His chest panel can open to carry the Rocket Monkeys, or to recieve any items from Dr. Chimpsky.
YAY-OK is very smart and he is quite the charmer. In fact, there is no ladybot that was on board that he hasn't made boop a little faster. But in the end of episode "Tail of The Unexpected", he become stupid.
Tasked with keeping the Rocket Monkeys on course, he likes them a lot and is there to help.
In "Princess Nefarious", at his first encounter with her, YAY-OK fell in love with Nefarious' robot Slo-Mo. He exchanged data with her and back on the ship they had a date and kissed. In "Party Planet", they went on a second date on Nefarious' asteroid, and later they went to the Council to Stop Supervillians' party, which was taken over by all the children.