The two most badass characters in history, they're from Gumby and both resemble wooden letter blocks with the letters J and G on them each, but some other letters and numbers can be seen in different episodes. G is usually seen as the leader of J, but they both slap each other often.
Guy 1: bro did you see what the Blockheads just did?
Guy 2: yeah bro they kidnapped an elephant, funniest shit I've ever seen.