For 40mm magnetic stir bars sourced from China, you will primarily find PTFE-coated (Teflon) cylindrical or olive-shaped bars designed for chemical resistance and high-speed laboratory mixing.

Key Features

• Dimensions: 40mm length, typically with a 7mm or 8mm diameter.
• Material: Chemically inert PTFE (Teflon) coating over an Alnico V or Neodymium magnet core.