NB 125-250 with material codes A/B/C/D/K/M/N/P/S forms the application for Grundfos 96658822. AQAV is the mechanical seal designation. The model and material-code sequence provide the pump-specific information, while the OEM number and AQAV identify the referenced seal for replacement enquiries. The KE MOTION HYDRO product associated with these identification details is NM-13.