The present invention is a shrinker stretcher machine that uses four distinct and separate tool cartridges to perform both shrinking and stretching operations by simply removing, rotating each tool cartridge 180 degrees, and reattaching it in its designated position. Each tool cartridge removably carries a jaw that can be removed and securely replaced with either a shrinker or stretcher jaw to accommodate the operation being performed. Each tool cartridges and jaw is firmly held in place by magnets and interlocking keyed surfaces to properly align and hold the tool cartridges and jaws.