The Flip-and-Go Stainless Mug is a super sturdy, easy to use travel mug. It is sold in a great variety of colors.  It is very easy to open and close and lock and unlock, with great buttons that are smooth to slide and work really well. The handle locks down when not in use but easily opens when you need it.  It is also great that it is made of BPA-free plastic and stainless steel.  The only downsides are that you can't put it in a dishwasher and you can't fill with dairy or fruit juice drinks because of the tight seal.  Also because it seals so well, read directions carefully to avoid injury.