This “sound machine” produces a gentle whooshing noise that will allow you to relax and fall asleep easily.
It can also be used during the day to mask distracting sounds for anyone requiring a quiet environment for concentration.
Sleep machine is fully adjustable for tone and volume and has two frequency levels for broader range.
This should really help on a trip to block out hotel noises. And what about people who put ticking clocks in their guestrooms to insure you won’t return too often?
Link here.