This is a Threaded Coupler for joining 4-40 size rods by Dubro.
Features: Polished steel construction
Includes: Two steel threaded couplers
Requires: Threading onto rod
Length: 36.5mm (1.438)
Diameter: 3.5mm (.138)
Length of thread: 18.5mm (.731)
Thread size: 4-40
Note: This coupler will join two 4-40 rods, with a male connection on one end and a female on the other.