The tag should say whether the nylon is coated or not, but an easy way to tell is to sprinkle water onto the nylon surface. If it stays on the top on the nylon, then it is coated. If it sinks into the nylon surface after a few minutes, then it is not coated.Any advice on the best vinyl to use on nylons. Some say they are only for UNCOATED nylon...how are you sure someting is "uncoated"? We would be doing nylon bags and jackets.