To provide a structure capable of detecting that a chemical
bottle unit is surely mounted at a prescribed position inside a device.SOLUTION: The present invention provides a chemical liquid
bottle unit configured by combining at least two bottles, the chemical liquid
bottle unit including a first bottle that stores a first chemical liquid and a second bottle that stores a second chemical liquid, the first bottle including an opening and a first container body that stores the first chemical liquid, the second bottle including an opening and a second container body that stores the second chemical liquid, the first container body including a first step portion for detection, the second container body including a second step portion for detection, the first bottle and the second bottle are substantially L-shaped, and when combined, the first container body and the second container body form a substantially rectangular parallelepiped shape.SELECTED DRAWING: Figure 7