The screw-on lid is a single piece and not two parts like the traditional mason jar lids used for canning. It creates an airtight container to package up favor gifts for your wedding or party guests, like honey, hand-poured candles, cookie mixes, salsa, bath scrubs, and more. The standard silver tin metal lid has a diameter of 2 3/8”, perfect for our 8 oz. favor jar, the cactus-shaped jar glass, and both the 12 and 16 oz. sizes of our mason jar drinking mugs. It’s a cute, cheap-priced add-on. The solid surface on top of the lid can be used for a round favor sticker, too, for additional personalization of your favors.