This is the Aluminum Ball Connector with Locking Sleeve from Sullivan.  
                                                                               
FEATURES: Machined aluminum construction                                       
          Anodized silver in color                                                
          Lifetime protection against wear                                     
          Permits full range of motion                                         
                                                                               
INCLUDES: One Aluminum Ball Connector with Locking Sleeve                 
                                                                               
REQUIRES: Installation on 4-40 rod or coupler