Vertex Water Cooler Filter Kit - RO Membrane Sold SeparatelyFilter Replacement Kit for Vertex PWC 400, PWC 500, PWC 600, PWC 1000, PWC 1010, PWC 1500, PWC 1800, and PWC 2000 Reverse Osmosis System (RO Membrane Sold Separately). Compatible with Vertex filter kit FK 104. The YS VERPWC is also the 1 Year replacement kit for PWC 400, PWC 500, PWC 600, PWC 1000, PWC 1010, PWC 1500, PWC 1800, and PWC 2000 on standard filtration systems without a membrane. INCLUDES: STAGE 1 1x Sediment Pre Filter (K5605 JJ) Replace