The fully tested and certified KMB-18B and 28B Band Masks may be used in mixed gas diving as well as shallow water diving. The SuperFlow adjustable demand regulators provide low inhalation resistance and high gas flow letting the diver breathe easier and work harder with less exertion. Both masks come standard with the large tube SuperFlow 350 regulator. The Side Block Assembly of both the KMB-18B and 28B receives the umbilical over the shoulder in the B configuration. They both come standard with the Tri- Valve exhaust system (Patents Pending), and the new patent pending Band Mask Band Keepers. The Tri-Valve Exhaust System (Patents Pending) has less breathing resistance than the older single valve exhaust. It retrofits to all previous Kirby Morgan Band Masks. The new patent pending Band Mask Band Keepers couple with the redesigned hood not only prevent any separation of the hood from the mask but also makes it impossible for the bands to separate from the mask. The communications connections can be either a male waterproof plug in type or bare wire posts. The KMB-28B Band Mask is very similar to the KMB-18B. Many parts on the KMB-18B are interchangeable with the KMB-28B. The major difference between the 18B and 28B is the material of the mask frame itself. The KMB-18B has a hand laid fiberglass frame (yellow) while the KMB-28B frame is an extremely durable injection molded plastic (black). The relative ease of the production of the KMB-28B frame allows for a lower cost and quicker deliver of this mask. Other differences include: 1) the main exhaust body of the KMB-28B is part of the frame itself and uses a #545-041 main exhaust cover, 2) no comfort insert is required on the 28, 3) the face ports for the 18B and the 28B differ slightly in size.