1.SO SMALL YET SO . How can two small noise devices create such havoc? These annoying beep pranks become your favorite of all pranks and practical jokes. Super easy to use. Simply turn them on, pick a sound and hide them. All that's left to do is watch and hear your victims lose their mind. 4.PERFECTLY TIMED INTERVALS. Lets face it, this might be the number one complaint form all others. Some go off way often, while others don't go off enough. If it off often it be easily found, if it doesn't go off enough it 't be annoying enough. We've timed ours perfectly, at least we think so. See interval chart in the pictures for on how often it sounds off. 3.MULTIPLE SOUNDS. Why Limit yourself to a sound machine noise device with only one sound? Ours have multiple different noise options. Two different annoying cricket sounds, a beep noise, and lastly a computer tech sounding something or other thing-a-ma-bob that is so annoying, it have people running for their sanity. 2.WHY OURS? Most other annoying beep prank noise makers 't last as long as ours. They use a battery that lasts a few days, we use a battery that lasts months and even years. Keep the beeping laughs going. Makes a great revenge prank, joke or gag. 5.HOW TO USE. Turn them on, pick a sound and hide them at a distance from each other for double the laughs. Once they think they have located the sound, the other one off and throws them off. Makes a great gag or any other work place location.