Brassket
A semi-standard unit of measurement achieved by placing the hands abreast, thumbs extended and connected with the pinkies extended. ( hang loose sign with thumbs touching ). If the girl's ass can fit in-between the tips of the pinkies, you are good to go.
Justin looked behind him and said, "Wow, that girl has a nice ass!"
Drew: "does she fit into the brassket ?"
Justin: " Yes, yes she does but only if my thumbs don't touch."
Brad: "I have bigger hands, she fits my brassket, you are good to go."