My review of this product: Less worry about your happy sleeping time. We are happy with this product especially if you don’t have your maid or family to help monitor the baby for all the time. If baby stopped breathing (we hardly know baby can just turn and not breathing), in 20 seconds the sensitive alarm is detecting it and the alarm will ring. To wake up baby as well as parents. Doesn’t work if you put the baby under the fan. Work well in the air-conditioning room.