The Dayton Superior Bar Lock® Coupler System provides a simple, quick, cost effective method for splicing smooth or deformed rebar in tension and/or compression applications. Bar Lock® couplers are effective when used as a "positional" coupler when the rebar is fixed in place or when the rebar is free to rotate. Bar Lock® couplers utilize lock-shear bolts and serrated grip rails to mechanically splice the rebar. The serrated grip rails are embedded in the rebar as the lock-shear bolts are tightened. The heads of the lock-shear bolts are designed to shear off at a prescribed torque to ensure proper installation.