We show that in macroscopic derivation of nonlocal material relation for a moving fluid,the involved local rest frame should be rotated with the fluid together.To determine the- relationship between the local rest and laboratory frames,outside the velocity,there will appear- three space angles in the set of state variables for the fluid.They satisfy three general equations.Although this work is given for a simple model of relaxation time,the provided approaches- are general,and applicable for obtaining more complicated material relations with dispersion and nonlinearity,which are invariant under the Lorentz transformation.