Made from medical PVC. Adjustable nose clip, with anti-crush 7ft,tubing. The masks are available with various oxygen diluters to accommodate child to adult patient. All masks are under the chin style, the diluter ID: 22mm. Complete diluter jets range from 24% to 50%: Blue 24%, white 28%, orange 31%, yellow 35%, red 40%, pink 50% and green 60%.