Adjustable Nylon Straps For A Perfect Fit. Harness Sizes Range From 3-4 Lb Dogs To 20-29 Lb Dogs. Comfortable For Small Dogs To Wear With Complete Control For The Owner. The Durable, Long Lasting Neoprene Mesh Material Is A Very Light Weight And Breathable For Comfort. Adjustable Nylon Straps For A Perfect Fit.