What a terrible font on the pail. I zoomed in to read it, but still didn’t realize that it said “graft” until I read your description/comment. I thought it said craft, which made no sense.

Oh, true. And it being a gym also supports the “ass” angle.

They didn’t say “a piece of,” just “a piece.” Since we’re talking about slang and since “a piece” is slang for “a gun,” we’re forced to conclude that the advertisement is for a gun shop.