Puli is a double-cap safety pill bottle. The outer cap is connected to the inner cap by tracks. In initial status, the outer cap can be rotated freely while the inner cap will not move. For adult, by pushing the outer cap, two caps will engage by the protrusion and depressions and can be rotated synchronously to open the bottle. For children, it is difficult for them to push the outer cap due to the narrower channel design, thus making the bottle safe.