SPECIALLY CALIBRATED FOR BIGGER DOGS: Available in Large, XL, Giant XXL. Too powerful for smaller dogs. CLINICALLY PROVEN: In a clinical study by University of Pennsylvania, owners of large dogs reported less pain, improved mobility, and higher quality of life after using a Big Barker for just 28 days. 10 YEAR WARRANTY: Foam will retain 90% of original shape & loft for 10 years or your money back. Won't flatten over time. MADE IN THE USA: Handmade by craftsmen and craftswomen in our Pennsylvania workshop.