works great [SEP] jeffs wife i have used the white name brand for years and some store brands but not the charcoal ones these work just as good as the others although i am not sure if the charcoal really makes a differencethe description photos show slits in the strip but i have not seen them in mine not a big deal but they do serve a purpose there is quite a bit of black residue left over there is also residue left over when using the white ones the black is just more visible but it rinses away easily with warm wateri am very happy with these