Note: HayeSep D is a higher-purity form of HayeSep Q porous polymer and has similar retention characteristics. HayeSep-D PLOT columns offer better performance characteristics compared to those produced with HayeSep-Q. For several years, VICI Metronics has used the higher-purity HayeSep D to make HayeSep-D/Q PLOT columns. Our HayeSep-D/Q columns are comparable to those produced by other manufacturers of Q-type columns. We have kept both product names for our customers’ convenience.