Review on Optimized Replacement Filter Kit for Vertex PT 4.0 RO System - Includes Carbon Block Filter, PP Sediment Filter, and Inline Filter Cartridge by CFS by Heidi Smith

THIS IS THE EXACT ORDER LAST YEAR. I used the reorder feature on the Amazon site. 2 out of 3 filters fit. Obviously the design of the 3rd filter has changed and is no longer suitable for our block. Nowhere is it indicated that the design of the filter may differ from your last order. Unfortunately, this was not discovered until after the first two filters were installed. So we just decided to replace two and throw away the third filter. Now I have to buy a replacement filter from the store, which costs me 33% more than ordering from Amazon.