Reinforced couplers USES 45 # fine carbon steels is made, has threaded shape silk clasp, tooth type ... 2010. Reinforced couplerThis coupler is a bar - for connecting bar rebar connection, reinforced (14mm - 40mm).Reinforced couplerProduct synopsis1. D14 - ... quality carbon steel is made4. HRB335 Sutiable HRB400 reinforced HRB500, rebar, and equivalentRelated testing1. Tensile strength = 1.1 x tensile ...