Both of these will remove undercoats, but they have different removal methods. The undercoat rake features small, sharp, curved blades set close together to remove the undercoat.  The undercoat rake can be used on wet and dry coats, and they remove fuzzy undercoats very quickly. Rakes are t-shaped with rounded pins that also pull out the undercoat, but you cannot sink the teeth too far into the undercoat, or you will hurt your pup. The length and shape of rake teeth will differ as well. For example, on most rakes, you'll find that the handle comes directly from the crossbar head with all the teeth. Undercoat rakes and rakes must be used carefully without too much pressure. If you tug too firmly while grooming, you could hurt your dog.