We have used the OFF circular deal and it has worked fairly well. Two years ago we were coming out of West Yellowstone and got stopped in a construction zone while waiting for the pilot car to take us thru. We struck up a conversation with flagger working the zone and noticed he had the OFF circular thingy on his shirt. He said it worked for him, but also told us he doesn't buy the new pads for in it, he just sprayed the OFF from the spray can into it and it worked just as well, sort of like refreshing the pad. We have since then done likewise and have had good results.