With the set of 4 stainless steel 170 mL cups it provides almost 6 fl. oz. to enjoy a small beverage or water when out camping. Perhaps a little bit larger than would be needed for actual drink shots, but if one likes to mix up a small cocktail it would provide enough space for not being served in more traditional bar glassware. I like the zip-up travel container to keep the cups in when not in use, it's something that can be easily marked when packing up with the rest of one's travel gear. Beverages stay cold or warm longer due to the metal cup. Also because of the cup material, one doesn't have to worry about dropping and breaking the cup. This is a nice set to have around, the only concern I had when receiving mine was that it was difficult to separate the plastic separator that was placed between each cup to prevent any scratches during shipping-- almost couldn't pull the cups apart at first to clean before their first use, but otherwise they function well for travel cups.