The 227-1221-11 is a die set, also known by its military part number M22520/5-11, designed for the Amphenol TWINHEX crimp tool system. This die set features two hexagonal crimp cavities, with a size of .213 inches (5.4 mm) for Cavity A and .068 inches (1.7 mm) for Cavity B. It is compatible with both the 227-944 hand crimp tool and the 227-60 pneumatic crimp tool. This die set is used for assembling specific Amphenol RF connectors in industrial and military standard applications.