What is rebar joint couplers and how do you connect two pieces of rebar?

Rebar joint couplers are used for joining rebars with full tension capacity. The ends of bars to be joined are provided with threads, and the bars are joined using a coupler sleeve that transfers the force on the rebar across the connection. Different types of couplers are available in the market, such as parallel-thread couplers, taper-thread couplers, bolted couplers, and grouted couplers. Rebar joint couplers are components which connect two reinforcing bars in longitudinal direction, forming a mechanical splice. Mechanical splices are used to avoid protruding bars in casting joints, reduce congestion in confined spaces and to save rebar length.