Features: Excellent PS material. non-toxic and anti-break. Well-sealed vacuum cups, not easy to fall off or drop when used. Top valve for easy pressure release. 3 sized cups: Interior Dia. 2.6; 2.3; 1.9 and each size has 2 cups. Equip with vacuum suction handle to adjust pressure on your needs. Safer than glass cups, no need of fire. CE approved, high quality product.