Abstract: A mask having a removable respirator, a viewing glass and flexible fastening straps on the rear side thereof is provided. The respirator and the viewing glass are fixed by respective fixing rings to suitable positions in front of the mask. The fixing rings are tightened by a screw having a turning grip formed on the top thereof, so that it makes possible simple disassembly without the use of tools. The screw is also provided with a flange adapted for convenient attachment of a speech microphone thereto.

Abstract: A valve for checking tire pressure comprising a hollow cylinder, a sealing block, a plate, a spring and a flute. The hollow cylinder has a flange inwardly extending at intermediate portion thereof to form an opening and divide the hollow cylinder into upper and lower portions. The sealing block is disposed in the lower portion of the hollow cylinder and contacts with the flange to seal the opening. The sealing block is provided with a passage communicating both sides of the sealing block. The plate has a pin downwardly extending into the opening and contacting the sealing block and a seat formed on upper surface of the plate. The spring is disposed on the seat of the plate. The flute mounted on the hollow cylinder includes a base and a flute body disposed on the base. A passage is formed in the base which communicates the flute body with the upper portion of the cylinder.