This is pretty self explanatory, I live in a large house and discovered someone was using my laundry detergent without my permission, I thought this would be a lot more effective than a passive aggressive note or something. The lid for the jug I put it on (seen in pics) fits so snuggly that I just leave the top part on when I untwist the cap to open it. It should be very simple to adapt to similar large sizes of laundry detergent.