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For over half a century, zeolites have played a major role in the development of modern processes in the chemical and petroleum industries. [1] Their unique combination of physical and chemical properties are ideal for catalysis and separations for a broad range of molecules. Recent advances in zeolite synthesis have centered on high silica zeolite systems or have employed exotic templates. [2] However, low Si/Al ratio zeolites are particularly attractive because they can offer high acid site density for catalytic applications and greater ion-exchange capacity and compositional diversity for separation processes. We report here our discovery of two new zeolite materials, UZM-4 and UZM-5, synthesized at low Si/ Al ratios (Si/Al < 10) by using combinations of two of the most common organic templating agents, the tetramethylammonium (TMA + ) and tetraethylammonium (TEA + ) ions. [3] UZM-4 is a large pore 12-ring zeolite with the BPH framework type [4, 5] and a sufficiently high Si/Al ratio (1.5-2.5) to enable thermal stability. UZM-5 has an unprecedented framework type that contains an 8-ring pore system similar