OVAL SUPPORT DISC KIT7MM, 8MM, 9MM, 10MM, 11MM, 12MM, 13MM DISCS. 6 OF EACH SIZE. The Support Discs are specialized, high performance fly tying components designed to act as a versatile foundation for creating articulated streamer and baitfish style flies. Specifically developed to complement the Game Changer hooks and shanks as well as the Beast Style fly, Bob Popovics designed. These discs (often referred to as "standard" or "oval" support discs) provide structure,