My game on Xbox potentially gives you two flashlights. Occasionally you need to stop using the tool to use a clickdetector (my port to Xbox was a tad lazy, but it works). However, if you have more than one tool you cannot deselect them.
Normally RB and LB deselect a tool, but if you have more than one then it just cycles through them. I am using a PS4 controller on PC but I cannot find the button to deselect a tool after cycling through every possible one, so this may be a bug or just me being stupid.