THERMOS STAINLESS STEEL COFFEE CUP INSULATOR KEEPS YOUR COFFEE HOT OR COLD WHETHER YOU BREW YOUR OWN OR STOP AT YOUR FAVORITE COFFEE SPOT. YOU SIMPLY INSERT YOUR CUP AND GO! TURNS MOST STANDARD 18 AND 20 OZ. COFFEE CUPS INTO AN INSULATED TRAVEL TUMBLER. KEEPS BEVERAGES HOT FOR UP TO 3 TIMES LONGER, HOT STAYS HOT FOR UP TO 2 HOURS AND COLD STAYS COLD FOR UP TO 10 HOURS. DURABLE STAINLESS STEEL.