The SomnoMed MAS™ is a Mandibular Advancement Splint (MAS) that treats both snoring and obstructive sleep apnea (OSA), by advancing the lower jaw forward. It is a custom-made device consisting of upper and lower dental plates with a unique patented fin-coupling mechanism.required, a component can be added to make the device adjustable. This feature provides incremental and adjustable levels of jaw advancement, which improves the effectiveness and comfort-level of treatment as the jaw is moved only as far as is required to alleviate snoring and reduce OSA.