The ALNICO magnetic stir bar withstands temperatures up to 250°C, making them suitable for use with both unheated and heated stirrers. Smooth shape for better coupling when using concave bottom glassware * Magnetic bar is made from ALNICO, one of the strongest permanent magnets available * The sintered manufacturing process reduces the chance of decoupling (spin outs), encapsulation in PTFE protects both magnet and what it is stirring * Chemically inert and easy to clean * Can withstand temperatures up to 225°C, making them suitable for use with both unheated and heated stirrers SPECIFICATIONS: * Autoclavable: True * Color: White * Dimensions (L x W): 1.4 x 0.3 in (35 x 8 mm) * Material: PTFE * Material: Alnico * Quantity: Pack of 10 * Shape: Octagonal cylinder