Key FeaturesMaterial: It is made from food-grade 304 stainless steel, which is rustproof and more durable than glass alternatives.Insulation: The device typically features a double-walled construction, which provides vacuum insulation to keep your coffee or tea hot for longer while remaining cool to the touch on the outside.Filtration: It uses a high-density mesh filter plunger system that effectively blocks coffee grounds or loose tea leaves, allowing natural oils and aromas to pass through for a rich, full-bodied flavor.