The design is pure genius of GSI. The plunger is the cup. No annoying rod poking your eye while drinking. There are no grounds that make their way around a flimsy screen. This is the perfected portable coffee press. A precision-engineered inner sleeve acts as a no-mess griddle and then becomes an extra wall of insulation to keep coffee or tea warm. The copolyester construction is unbreakable and BPA free. Secure top seals in heat and helps prevent spills. An insulated sleeve wrapped in rPET adds warmth and protects your hands. and everything fits perfectly in your cup holder. Sleeve fabric designed with rPET helps reduce waste