PACK OF 2. Replace damaged diaphragms on the Annovi Reverberi AR813 or AR1064 Diaphragm Pumps with this Annovi Reverberi BlueFlex Diaphragm # AR1040083. BlueFlex material redefines how durable a diaphragm can be, even under tough operating conditions. To extend diaphragm life, the BlueFlex diaphragms have a special shape and thickness that have been carefully optimized to reduce mechanical stresses during the working cycle of the pump, even under difficult working conditions. Its new patented diaphragm retaining plate has a shape that minimizes the chances of the diaphragm becoming caught or nicked by the diaphragm plate.