The BQQV-designated mechanical seal Grundfos 96658816 is listed against NB 125-250 with material codes A/B/C/D/K/M/N/P/S. The codes belong to the pump application description. Preserve them as written alongside the model when using the Grundfos number to identify the corresponding seal reference. This identification is linked to KE MOTION HYDRO product reference NM-13.