Versatile Magnetic Stir Bar Set: This 8-piece PTFE Magnetic Stir Bar set includes 8 different sizes, providing perfect options for various laboratory applications. Material: Polyethylene tetrafluoroethylene (PTFE) magnetic stir bars are made by sealing permanent magnets in PTFE material can withstand high temperatures. Perfect for Laboratory and DIY Use: Ideal for laboratory applications such as chemistry labs, general training, , also a good choice for the home diy handmade project. How to Select: Select the stir bar based on the volume; For volumes up to 1000 mL, a 15 mm stir bar is sufficient. For volumes up to 3000 mL, a 30 mm stir bar should be used; Note: Stir bars are suitable for use with liquids of low viscosity. If used with thick, oil-like liquids, the stirring efficiency may be affected. Ideal for Flat Bottom Container: This cylindrical with shaft ring shape stir bar set is suitable for use in flat-bottom containers. Color: White Material: PTFE Package Contents: 1 set x Magnetic Stir Bar Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.