Impeller assembly for micro-carrier spinner flasks. Consist of magnet holder, silicone plug, magnet, and ptfe paddle. Impeller size: 1-3l Paddle dimensions: 1 3/4" x 4 1/4" Consist of: Magnet holder: a523-207 Silicone plug: a523-200 Magnet: 1975-0300a Ptfe paddle: a523-206