The DUO has been purposefully designed to ensure ease of use and that carrying should be no trouble. Both grip and stability are aided by the DUO and you can enjoy your drink more easily without having to be in any discomfort whatsoever. The beauty of the DUO is that it adapts items you already have so you don't need to buy a new mug or glass, you can simply attach to those you have already. What's more, the material it's made from also protects your fingers and hand from the heat of a hot cup. As a new product on the market, the DUO has appealed to many at trade shows and is gaining in popularity and we completely agree that it really is a valuable invention which solves an age old problem.