The MEC Mayville Engineering INC 8447410, also known as the 600 Jr. Mark V single stage reloader, caters to both beginners and experienced gun enthusiasts. This trusted product has been renowned over the years for its efficient, effortless operation.Its defining feature is the cam-action crimp die, which expertly restores each shell to its original condition. Furthermore, the process of positioning wads is a breeze. The MEC 600 Jr. Mark V is not only quick, but also productive, capable of loading 8 to 10 boxes per hour. It is designed to be adjustable to 3\" shells and is specifically for 410 Gauge.