Hario's double-wall stainless steel carafes are perfect for keeping your pour over brews warm for up to 90 minutes. These thermal servers feature a pour-through lid with a lever actuated opening, so they keep the heat in until you're ready to pour. The server's opening is designed with V60s in mind, but it can accommodate many other pour-over devices like the Kalita Wave. When preheated with hot water, this 550 mL carafe can keep a fresh brew hot for up to 90 minutes. Our temperature data showed that a fresh, 180 F brew was still hovering around 160 F at 60 minutes, and 140 F at 120 minutes. Compare that to the same drop in about 15 minutes in a standard glass server, and you've got a lot more time to enjoy your brew!