The SOMA SINUS SODIAL Positive Displacement Pump works according the SOMA SINUS SODIALĀ® PUMP principle, which was developed by Manfred Sommer in 1982. This Sinus pump, available in long-coupled (CRN) and close-coupled versions (CRN-D), is distinguished by its extremely gentle pump action, powerful suction with low-shear and low pulsation. This pump can overcome the limitations of conventional rotary lobe pumps in many applications.