This mask is a Tangfeng brand double-tank filtered gas mask, suitable for workers in industrial, agricultural, and research institutions who are exposed to organic vapors, benzene and its derivatives, gasoline, acetone, carbon disulfide, ether, and other substances.

1. Structural Features:
The main component of this mask consists of four parts: the filter box, breathing valve, and straps. The main part is designed according to Chinese facial shapes, while the straps can be adjusted in tightness as needed. The mask has good density, making it safe and comfortable to wear.
Packaging: Each unit is packaged individually, and 40 units make a box.

II. Technical Indicators:
1. Total weight of the mask: <250 grams.
2. Exhalation resistance: <4.9 kPa.
3. Inspiratory resistance: <7.8.0 Pa.
4. Poison prevention time: >50 minutes.
5. Air leakage coefficient: <5%.
6. Harmful space: <170 centimeters.
7. Field of view: >35 degrees.

III. Usage:
1. The usage conditions for this mask are: the concentration of toxic gases in the environment should not exceed 0.1%, and the oxygen concentration in the air should be at least 18%. The ambient temperature should range from -30 to +54 degrees Celsius.
2. This mask cannot be used in working environments with sealed containers such as tanks, and is also not suitable for use in other gas filtration environments.
3. Before using the mask, check whether all components are intact, whether the exhale valve disc and the bottom of the valve are sealed, whether the filter box is tightly attached to the main body, and whether the filter material inside the filter box is loose.
4. The mask must be worn properly, covering the mouth and nose completely. There should be no gaps on either side of the nose bridge. The straps of the mask should be tied securely, adjusted so that the mask does not loosen, does not press on the face or nose, and does not leak air.
5. During use, when the filter loses its effectiveness, a slight odor of toxic gas may be detected in the mouth and nose. The user should immediately leave the area with toxic gases, replace the filter with a new one, and if necessary, recheck the tightness of the mask.

IV. Maintenance:
1. Replace with new gas filter; install it according to the original installation sequence. The filter must be filled completely to prevent gas leakage. After installation, tighten the box lid securely. Gently shake the filter to ensure no friction sound is heard inside.
2. Masks and gas filters should be stored in a clean, dry place with appropriate temperature.