We booked a beach vacation in Pacific Beach near San Deigo, CA. We did not realize we were one block off the main street where the action went on till 3 or 4 am. With young boys we thought the vacation was lost. However the owner had these in each room. We found that we slept through a week of nights filled with late night revelry and with the police rousting drunks and lagards. Back at home, we got them for all bedrooms. Now we and our boys stay asleep all night.