It was a small vacuum chamber, about the size and shape of a bathtub stopper, that contained a plunger and spring, and had two small airhoses attached to it.
它是一款非常小巧的真空管，形状和大小如浴缸塞，内含一个柱塞和弹簧，由两个小型空气软管连接。
2
Crowfoot connections on airhoses shall be wired or otherwise secured to prevent accidental disconnection. Compressed air shall not be used to dust off hands, face or clothing.