Tide Washing Machine Cleaner has been specifically designed to help remove and dissolve away odor causing residues that may build up in your washer over time - even from those areas you can't see! Have you ever run a load a laundry and at the end, it just doesn't smell clean & fresh? It could be coming from residues left behind in your washer. Washers today use less water, which can leave behind residues in machine -including areas you can't see, e.g. back of the tub, hoses, drain, etc. These residues can lead to the build-up of malodor, which can be transferred to your laundry.