It is specially used in negative pressure ambulances to avoid the leakage of polluted air in the car, and to purify the internal air and discharge it to protect the environment outside the car. It is a safe device. In the face of this new coronavirus, we can all see the bitterness of medical staff

"After working for a while, my cervical vertebra is so uncomfortable!" Is this sentence often heard? At present, cervical spondylosis has become a "modern disease". For this reason, there are "cervical vertebra traction devices" on the market. The most common cervical spondylosis we used to go to m