Made from SUS stainless steel, which resists corrosion, staining, and most importantly, doesn’t give you a metallic taste in your mouth. Vacuum sealed, super light at only 8 ounces. One piece design, no seams or welding. Holds 16oz of liquid, dimensions about 8 or 9 inches tall, by less than 3 inches in diameter. In typical Piao I fashion, the filter rinses clean and is very fine. One model has a screw-on cap, the other has an innovative pop-up lid that can lock. It only takes about two or three turns to screw the filter cap on. The filter pops in and out, with a satisfying click. You can pour through the filter. We have found it the perfect size for brewing tea, herbal tea, or can even be used for coffee. Certified Plasticizer and BPA free by SGS Taiwan. All in all, the best brewing thermoses that has ever been invented.