This is a Kwik Grip E/Z connector set by Dubro. EZ Connectors link a pushrod to a servo arm allowing it to pivot for less bind in control surfaces.
Includes: Two each of brass EZ Connectors, two plastic snap nuts, two metal snap nuts and two 2.5x3.5mm slotted head screws
Requires: Assembly onto linkages and Kwik grip E/Z connector wrench
Length of brass connector: 10mm (0.395)
Diameter of brass connector: 5.5mm (0.217)
Note: These differ from the standard E/Z connectors DUBQ1860 in that they have a hex shape for easy tightening.