Surfboard event and PSB

They're not the regular PSBs, they're Super Summer PSBs! Slightly higher base attack is the only difference I believe. I found like 10 at Mutant Pigs hunting for familiars, they're fairly common. They drop from mobs and come from the ice chest things that drop too. I would assume lower level mobs drop the lower level ones but I don't know for sure, since none of them show up on the Codex drop list.