Hip Flasks, especially engraved hip flasks are one of the most popular items amongst engravers and its clear why. Available in an almost infinite range of styles, configurations, materials, colours and are easy to sell. One reason they might be so popular might be the side of naughtiness they are associated with. Made popular during the US prohibition period to secretly move alcohol around or sneak it in to a drinking establishment as maybe the case these days. Part from this they generally make great gifts that can just sit happily on a shelf or area of the home as a display piece.