OPTIMAL DRINK TEMPERATURE: Our honeycomb-insulated Press-In Lid replacement ensures cold drinks stay chilled and warm beverages remain hot for hours QUALITY & SAFETY: The lid is crafted from silicone, making it easy to clean and dishwasher safe IDEAL FOR MEDIUM-SIZED CUPS: This medium-sized Press-In Lid is perfect for our 355 ml (12 Oz) Mug and 473 ml (16 Oz) Tumbler SAFE MATERIALS: Made from silicone, the lid for your HYDRO FLASK is easy to clean and dishwasher safe. Note that this model is not leakproof. SATISFACTION GUARANTEED: We offer a lif etime warranty against manufacturer defects. HYDRO FLASK stands behind our durable and robust materials and is committed to high standards.