Where is the throttle valve of the accumulator air respirator?

Located in front of the intake manifold

It is a self-contained and open fire fighting air respirator, which is mainly used in fire fighting, chemical industry, ships, petroleum, smelting, factories, mines, laboratories and other places, so that firefighters or emergency rescue workers can safely carry out fire fighting and rescue work in a harsh environment full of smoke, toxic gas, steam or lack of oxygen.