Kerlix is a Kendall proprietary product, sort of a premium product. Used when you expect a lot of drainage, or want to put some pressure on the wound. Might be on sale cuz they have a new, improved version that is impregnated with an antiseptic, which prevents bacterial colonization of the bandage. Might be a wonderful improvement, might be a marketing ploy. Usually the dressing is changed a couple times a day, and the wound cleansed, so bugs on the bandages isn't a real big deal. Probably be a good thing to wrap the salmonella tomatoes in, tho.