Due to a change in the manufacturing process, GA3446-20 "Corning Membranes, pack of 20" will now be shipped in 2 packages of 10 instead of 1 package of 20. However, the price and the catalog number will remain the same.
This manufacturing change involved the backer material of the PTFE membrane which was previously non-woven PTFE and is now non-woven polyester. At the time of this manufacturing change, it was also desirable to increase the thickness of the PTFE material serving as the ring gasket around the edge of the membrane assembly. This improved the rigidity of the overall membrane assembly during the manufacturing process and during general handling. The increased thickness does not affect the fit of the membrane assembly into the Corning Accelerated One-Step Liquid-Liquid Extractor (Cat# 13318), but it did change the packaging of the product. With the increased thickness, 20 membrane assemblies can no longer fit into one package. Today we have 10 membranes per package and still provide a total of 20 membranes for each GA3446-20 ordered.