Review on ☕ Cahlis Travel Coffee Maker - Portable Pour Over Coffee Maker with Thermal Cup - Vacuum Insulated Stainless Steel Cup and Paperless Filter Dripper - One Cup Pour Over Coffee Maker for On-the-Go by Lori Harper

Good size and good insulation. The top and clasp are well made and practical. Definitely leakproof. Rubber sides, when the balloon is very nimble, it won't slip. The only drawback would be the metal filter. It fits over the cup when filtering coffee, but what do you do with it when you're on the go? If there were a way to attach a metal filter to a cup (after removing the coffee grounds) so that it becomes a single self-contained device, it would be very practical and smart.