The sinuses are air-filled cavities. 1  They are located: 2  Within the bony structure of the cheeks. 3  Behind the forehead and eyebrows. 4  On either side of the bridge of the nose. 5  Behind the nose directly in front of the brain.
An O-ring is a round ring that is used as a gasket for sealing a connection. O-rings are typically constructed out of polyurethane, silicone, neoprene, nitrile rubber or fluorocarbon. These rings are commonly used in mechanical applications, such as pipe connections, and help to ensure a tight seal between two objects. O-rings are designed to be seated in a groove or housing that keeps the ring in place. Once in its track, the ring is compressed between the two pieces and, in turn, creates a strong seal where they meet.
O-ring face seal ï¬ttings. Seal-Lok Liteâs leak-free, compact. design makes it suitable for use in applications for low pressure. gases and general light duty industrial systems. Design and Construction. The Seal-Lok Lite ï¬tting consists of four main components: a. body, a sleeve, an O-ring and a nut.