Designed to fit into beakers and flasks with narrow necks, our folding lab impeller is the perfect impeller for your laboratory mixing. In the folded position these impellers have a diameter of less than 5/8" allowing them to fit inside your 24/40 joints. When rotated, centrifugal force raises the blades which open and create radial flow. Constructed of 316 stainless steel, these folding lab impellers provide a high level of chemical and abrasion resistance.