New Brand & Color: Blue Quantity: 1 Pcs You are looking at foam filters that are compatible with many models of inflatable hot tub. Be warned that you will see many distorted versions of these filters for the same price as a square or hexagon. They have this shape because they are cheap and of course they are not as well fitted as round types that give a more consistent surface. They are also extremely thick, which of course restricts the flow of water, causing excessive stress on the pump. They are much cheaper than the original filters, much more casual and I find they filter much better. I was able to source round filters rather than the cheaper distorted ones that are for sale elsewhere. They will filter water much better due to the constant surface area and have been proven to be a better fit. These filters require more attention and I recommend using bromine because this chemical is odorless, cheaper, better for your skin and much more filter friendly if you decide to use chlorine I strongly recommend changing these filters weekly note these filters will lose some color through use. This is completely normal and there is nothing to panic about.