Pool Frog Mineral Cartridge 5400 Series Swimming King Technology. Thank you and Happy Holidays. NOTES: This Mineral Reservoir is the 5400 model, not a replacement for the 6100. They look very similar, and I don't want to send you the wrong item, Thank you. Please contact me, if you have any issue or concern after receiving your product.I will make it my first priority to resolve any issue you bring to my attention. If you write outside those hours and don't get a response, I will contact you the next day. The item "Pool Frog In Ground Mineral Reservoir Cartridge 5400 Series Replacement" is in sale since Wednesday, May 19, 2021. This item is in the category "Home & Garden\Yard, Garden & Outdoor Living\Pools & Spas\Pool Chemicals & Testing\Pool Chemicals & Clarifiers". The seller is "amstore333" and is located in Woodland Hills, California. This item can be shipped to United States.