Right now there are 240 deals from Amazon Resale, formerly Amazon Warehouse Deals, in Patio, Lawn & Garden › Pools, Hot Tubs & Supplies › Filters & Filter Media › Filter Cartridges & Media › Pool Filter Cartridges. These are inspected returns and open-box items that Amazon sells and ships itself. WarehouseHunter puts each one next to its current new price, so you can see what you save at a glance.

Brands with the most offers here: POOLPURE, Cryspool, Hayward, Pentair, Jandy, Pro, Malaka, System. Every item is a one-off, so the stock moves all day and new deals keep arriving.