Ive tested it on my own shirt or dress multiple times to see if it picks up everything and the most amazing thing is to see how it registers that ive turned to my left or rightdefinitely more sensitive than the movement monitors i had used in the past for my daughter admittedly 18 years ago but this product is easy fantastic and makes me feel completely comfortable knowing it will pick up his breathing and movements like i want it to when he eventually settles into his crib instead of being in the bassinet next to me although i plan on using it there too