Help soothe and calm your new puppy or kitten with the melodic vibration of a mother’s heartbeat. The ingenious design of the Mother’s Heartbeat Heated Pet Bed by K&H creates the soothing feel and sound of a maternal heartbeat. Comes in 3 different heartbeats per minute based on breed sizes. Plus one for kittens! Included with each cozy bed is a K&H Pet Bed Warmer, a double-sided pillow, and a heartbeat device. Heartbeat device can be installed in either the pillow or the bed. Batteries included. Based on estimated heartbeats of the breed of the parents and puppy/kitten. Small breed, up to 20 lbs. Medium breed, up to 80 lbs. Large breed, over 80 lbs. MET listed. One year limited warranty. Sizes: Small (11" x 13" 4W), Medium (13" x 16" 4W), and Large (16" x 20" 7W).