This is the original white Deluxe Chin Strap by Philips Respironics and is the preferred choice for people who require a wider chin strap. The main strap measures approx. 3" wide x 26" long. The Chin Strap helps to prevent air flow leaking from the mouth by holding the chin in an appropriate position which encourages breathing through the nose. Mouth breathers tend to use these chin straps with nasal masks to prevent mouth breathing, which results in dry airways and reduces CPAP therapy effectiveness.