Solas DynaFly Impeller - Pitch 14/21 YS-DF-14/21 New impeller is designed to give high compression ratio pumps a stronger acceleration with less cavitation. This impeller is capable of giving your PWC an incredible boost in its performance. The SOLAS product line includes Dynafly impellers for the Kawasaki Ultra 150pump and the Sea Doo 951 pump. SOLAS also has developed new impellers for other pumps.