TenJan Mechanically bolted Coupler provides a cost effective method of jointing reinforcing bars, particularly when the fixed bar is already in place and there is insufficient place for a hydraulic swagging press. They are easy to install and suitable for yield strength of grade 500 reinforcing bar. Neither bar end preparation to form the thread, nor bar rotation are required.t Mechanically bolted couplers can also be used to join imperial, plain round or deformed reinforcing bars.