I have purchased from Amazon numberous times and never felt strongly enough of a product to write a review - up until now. I purchased this for my sister who has a very difficult time getting up. I received this and it is extremely cheaply made. It is cheap plastic. Yes the alarm is loud, and yes the vibrating disc is quite effective. However, I cannot see this working too long given the poor quality of this product. Also, mine did not operate under battery backup power. So - this needed to be returned anyway.