A Type of Impeller for Gas-Liquid Mixing and Impeller for Gas-Liquid Mixing has gotten two Certificates of Utility Model Patent again
2006 / 09 / 15

ZL 2005 2 0070185.X   A Type of Impeller for Gas-Liquid Mixing

ZL 2005 2 0070184.5   Impeller for Gas-Liquid Mixing