No, this thing is not dangerous, it is a next generation neck massager. It will gently vibrate once you place it around your neck (it is open in the front so you can easily take it of), perfect after the stressful day at work or at gym. It features adjustable vibration, Far Infrared Rays (F.I.R.) heat and low-frequency electrical impulses and you can turn these on individually or in various combinations. F.I.R. heating will provide a gentle warmth that penetrates bone and muscle tissue and will ease aches and tension in hard-to-reach neck muscles.