The Pro Co "The RAT" is a guitar effects pedal produced by Pro Co Sound. The original RAT was developed in the basement of Pro Co's Kalamazoo, Michigan facility in 1978. Numerous variations of the original RAT pedal are still being produced today.The basic RAT has changed in appearance over the years, but its tone has remained largely the same, although there is a general consensus that the mid-1980s versions are superior sonically.