Solution characterization of four samples of high molecular weight linear polystyrene (HMWLPS) in the molecular weight range of 1.61 × 106to 9.71 × 106in methyl ethyl ketone (MEK) at 25°C. was assessed from light scattering (LS), viscosity, and small-angle x-ray scattering (SAXS) under five different entrance-slit (E) /counter-slit (Z) combinations of 20/50, 30/75, 60/150, 100/250, and 150/375 μ, using the Kratky camera. The molecular weights and radii of gyration (<S2>1/2) obtained from SAXS under various slit combinations were then compared to the values obtained from LS. Further, the calculated values of<S2>1/2based on the theoretical relationship between size, entrance-slit and counter slit openings were compared to he experimental values of <S2>1/2of each sample. Thus establishing the upper limits of size for a given E/Z combination.