A mug rug is not exactly a coaster. A coaster implies that there is a water barrier in it. Like a placemat, it does not have a water barrier, functions like a placemat, but is just smaller. When I sell mine, I put them in a cellophane envelope and include a little explanation in the bag. That way, if it it is purchased as a gift, they will understand what it is used for. When selling them, having the explanation in the bag helps buyers know what they are so you don't have to repeat so much. However, buyers buy more when the seller interacts with them.