The SE 6 oz. Stainless Steel Hip Flask - HQ6 is perfect to give as favors or gifts at birthday parties and bachelor/bachelorette parties, or to use for camping, outdoors, and sporting events. This simple design is classic on its own or can be easily engraved. The mouth diameter is 1/2". SE Intellectual Property Rights Notice: Important: Avoid getting counterfeit items. Genuine SE products come with the SE logo on the packaging. SE is a registered trademark protected by US Trademark Law.