Hidden Cellphone Jammer
This cigarette pack device is your best bet to prevent disturbances or noise from phone blabbermouths at short distances.
This jammer is ready straight out of the box for instant jamming and unjamming. Use this mini portable cell phone signal blocker wherever people are likely to be rude and obnoxious with their cellphones like the theater, train, meeting rooms, class.
May not be legal where you live (and banned by the FCC in the U.S.), so use covertly & discretely.