The “Thermavest” product developed by Rene Boucher (the assailant) in 2003 seems to be defunct, or at least its website has become internet roadkill:
From a description someone else here of FR provided, the “thermavest” is a variation of a product called “Bed Buddy” I bought in Maine many years ago. Basically, it was an athletic sock with rice inside. It was sewn closed at the ends with a polypropolene loop at each end. About 14 inches long, it would lay nicely over one’s shoulders or across a knew or other body part. It was heated in a microwave. If I recall, it was a patented product. I have three of them. They work great.
Don’t be surprised if the wacko perp offers up one of his Thermavests to Rand Paul for the rib pain.