Material: Liquid silicone Size: 19*19*11cm Special note: This product can not be used alone, need to be paired with oxygen supply system and oxygen cylinder input oxygen. Product features: Liquid silicone wrap adhesive PC mask body two parts The headband is comfortable to wear and easy to remove; Soft and comfortable liquid silicone, high definition mirror; Both sides can open and close the air outlet valve; Compatible with all respiratory equipment, strong airtight; Ventilator connector universal 22mm diameter interface; Breathing joint can rotate 360 degrees; Application: respiratory protection, industrial protection, industrial field, laboratory. ITEM LIST: 1 set* (1 PC cover, 1 liquid silicone, 1 elbow buckle, 1 strap)