Every dog groomer will tell you that even the best pair of clippers will underperform without the right blade attached to them, and the right blade for the job can vary greatly on breed, coat condition and even the weather. Blades differ in both size and material, with each blade given a number indicating the length of cut. Larger numbers trim hair shorter than lower numbers, with a #7 blade leaving about 1/8” of length. #7 blades are great for an all-over summer cut on the body of the animal, especially on mixed and wire coated breeds. Blades that have an F in their number, like the 7F model, cut the same length but result in a smoother finish and are usually used on thinner, softer hair or to add a finishing touch to recent shearing.