Ultra Choke-free Harness - Skydiver Blue Lg (Chest 16-25") The Ultra is the perfect design for use as a Auto Seat Belt Harness. It pulls only from the chest, which is the strongest part of the dog and NOT the neck area. Double D-Ring for Added Strength. Made in the USA! Patent pending. Simple and Easy Step In Design, Wrap Up and Close Available in 16 colors and prints. Available in sizes XS/S/M/L Size Chart: XS: Chest 10-13" / 3-6 lbs - Sm :Chest 13-16" / 6-11 lbs - Med: Chest 16-19" / 11-16 lbs - Lg: Chest 19-21" / 16-25 lbs.