Pack of 3 - Hypro 9910-650671 BlueFlex Dampener Diaphragm. Replacement diaphragm for use on the Hypro D30, D50, or D70 Diaphragm Pumps. Also called a suction diaphragm, this Hypro BlueFlex Dampener Diaphragm is designed to help even out or regulate output pressure. It is manufactured with BlueFlex material, a new and innovative type of diaphragm material that establishes a new benchmark for diaphragm durability, even under the toughest of working conditions. The shape and thickness of the BlueFlex diaphragms have been carefully optimized to reduce mechanical stresses during the working cycle of the pump, even in difficult working conditions. Its patented diaphragm retaining plate has a unique shape that reduces the chances of the diaphragm being caught or nicked by the diaphragm plate. NOTE: The Hypro 9910-650671 Dampener Diaphragm can replace or upgrade the 9910-650670 Buna Dampener Diaphragm.