Abstract: A sucker rod having improved coupling capability for joining successive lengths of sucker rods in a string has a pin end coupler on one end and a box end coupler on the opposite end. The string is formed by inserting the pin end of one rod directly into the box end of the successive rod without the need of an intermediate cylindrical sleeve. A method of refurbishing the threaded end portions of used sucker rods involves cutting off the old threaded end portions and rethreading the rod ends. An internally threaded pin end coupler is then secured on one end of the rethreaded rod. An internally threaded box end coupler is threadedly secured on the opposite end of the rethreaded rod.