Carboy Carry Harness Strap For 6.5 Gallon Glass Big Mouth Bubbler - Fits First Generation & EVO2 Big Mouth Bubbler Fits first-generation glass Big Mouth Bubbler Carboys Fits Glass EVO2 Big Mouth Bubbler Carboys Big Mouth Bubbler not included. Harness Only! The Big Mouth Bubbler Harness can be grabbed anywhere on its adaptable frame without worry of slippage. The Harness holds tight to its Big Mouth passenger- keeping you and your Big Mouth Bubbler safe, however you prefer to handle it.