Teflon Propeller Paddle With Flat Holes For Benchmark 20L and 40L Overhead Stirrers, 1/EA. The Benchmark Scientific Optional Propeller features a Teflon paddle with flat holes, designed to meet your laboratory mixing needs. This propeller offers efficient mixing performance with its innovative design. Compatible with select Benchmark Scientific overhead stirrers, it provides reliable and consistent stirring for various applications. The Teflon construction ensures excellent chemical resistance, making it suitable for use with a wide range of substances. The flat holes on the paddle enhance mixing efficacy, ensuring thorough blending of samples. Upgrade your stirring capabilities with this high-quality optional propeller, ideal for research, pharmaceutical, and industrial laboratories.