Stick on UTH

[End Times]

Has anyone ever used a "stick on" UTH with their ball? After asking around I had people telling me that perhaps they would be a safer bet as apparently they are meant to be on 24-7 whereas human heating pads are not. I hesitate however due to the fact that these "stick on's" have no way of adjusting their temp... at least the human kind has low, med, and high...

Are these things safe, or am I right to be leery of such a product?

Thanks!