Stop problem barking, chewing, and anxiety in your dog the natural way.  ThunderShirt Sport's patented design applies a gentle, constant pressure that has a dramatic calming effect.  Designed for comfort, the breathable jacket features washable durable fabric, with contrasting trim and reflective logos for safer nighttime walks.  Using pressure to relieve anxiety in people and animals has been a common practice for years such as swaddling infants and the use of gentle pressure and weighted vests to help people with autism.