Aug 05, 2021 · 3 Layer Septa. Hamilton. Three Layer Septa is made of preconditioned silicone rubber and is 3.81 mm (0.150 in.) thick. The average life of these septa is up to 100 injections with a 26s gauge needle. The maximum operating temperature is 200° C. Preconditioned silicone rubber septa, 3.81 mm (0.15“) thick .