KeepCup Helix is Keepcups first fully sealed, twist fit reusable cup. The dual plug mechanism seals the lid from underneath and the top. Easy to twist together. Easy to twist apart for cleaning. Made from double-walled, insulated stainless steel, with a fully sealed twist-fit sipper lid comprising four parts. Easy to assemble and easy to clean. 1 hour hot, 6 hours cold. KeepCup Helix Thermal Nitro L