a frac nut assembly and method of using the assembly . the assembly has an annular shape , an outer circumferential surface , an interior surface having female threads thereon at one axial end of the frac nut assembly and a shoulder that extends radially inward from an opposite axial end of the frac nut assembly , and at least two lugs radially protruding from the outer circumferential surface . the frac nut assembly further comprises at least two members that define the frac nut assembly when assembled together at planar radial interfaces .