A glass puller is a laboratory instrument used to create fine, tapered glass micropipettes or microelectrodes. The choice of filament for the glass puller is crucial, as it directly influences the heating element's performance and, consequently, the quality of the pulled glass. Different types and shapes of filaments can be used, and the selection depends on factors such as the desired pipette.

• Filament, platinum/iridium
• Variety of sizes

The box filament is configured in the shape of a square, allowing for controlled heating in the corners or along the edges of the filament. Similar to other specialized filament shapes, a box filament allows for controlled and localized heating during the glass softening and pulling process. Box filaments are often used when researchers require capillaries with specific shapes or features.

The controlled heating in the corners can lead to unique geometries in the pulled capillaries. In microfabrication and microfluidics applications, capillaries with square or rectangular cross-sections may be desirable for certain experimental setups. These box filaments are constructed from a platinum/iridium alloy, which is known for its high melting points, corrosion resistance and biocompatibility.

Platinum-iridium filaments are suitable for pulling glass capillaries in applications where corrosion resistance is critical, such as in biological and medical research. These filaments are more expensive than tungsten or nichrome filaments and may require careful handling to avoid damage. You can choose the box size of 2.0, 2.5, or 3.0 mm, and the filament width for 1.5, 2.0, 3.0, and 4.5 mm. These box filaments may be used in the PUL-1000, P-1000, P-2000, and the P-97 microelectrode pullers.