This is an EZ Connector set by Dubro.
EZ Connectors link a pushrod to a servo arm allowing it to pivot for
less bind in control surfaces.
Works on 2-56 and smaller wire (.078")
Permanent or snap on mounting push nuts both included.
Two brass EZ Connectors
Two plastic snap nuts.
Two metal snap nuts.
Two 2.5x3.5mm slotted head screws.
Assembly onto linkages
Length of brass connector: 10mm (.395")
Diameter of brass connector: 5.5mm (.217")