100% and . It has good elasticity and can be used repeatedly. Overall good workmanship,quality assurance,the use of a unique absorbent elastic material fiber manufacturing process,environmentally friendly materials. It is a universal headband that can be for each type of nose mask. The headband is a versatile headband of nose pieces, the headband is made of three layers of heat sealing material, durable and durable waterproof non-. Instructions: When wearing the headband of the four non-piercing the buckle into the mask of the two perforated and two hooks will be worn on the head mask to adjust the hook on the elastic hanging, that is worn to complete, the user can rest that use. Specification: Name:Ventilator mask headband Colour: black Material: nylon fiber Size: About 75x13 cm Package Contents: 1 x Ventilator Headband Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.