Blowhard Sandstone is Fred Flintstone's rival, a bowling champion and a one-time character of the episode, "Barney the Invisible", featured in the third season of the original series, The Flintstones.
Blowhard is an obnoxiously boastful and arrogant man who never loses a game in his life and seems to have some sort of bad luck "hex" over his rival, Fred Flintstone.
Blowhard is a stout caveman with fair skin, tan stubbles, a bald head with two tufts and two strands of black hair, a triangular-shaped nose and thick black moon-shaped eyebrows. He wears a plum purple loin cloth with a black bow-tie.
- "Barney the Invisible" - (only appearance)