Double-layer magnets are used in the Rocker MF series magnetic filter holders to create a tight seal between the funnel and the support base. The user-friendly design allows for one-handed operation while preventing membrane twisting and ripping. Filtration Area: 9 cm x 17 cm Funnel Size: 9 cm x 17 cm. Compatible with a variety of bottles; vacuum flask with or without side arm for direct filtrate collection. Simple to use: A strong magnetic seal enables one-handed operation while preventing membrane twisting and ripping. The membrane guide on the base makes it simple to position the membrane. The PES (polyethersulfone) structure is resistant to a wide range of chemicals and high temperatures, as well as being robust and unbreakable. Reusable: Withstands multiple autoclave cycles, saving money and energy. Applications: Aseptic filtration, pharmaceuticals and biologics, suspended solids testing for municipal, surface, ground, and drinking water. Rocker MF Series is optimized for microbiological testing. Additionally, the lid on KP 47U can be vented aseptically using a disposable syringe filter (luer slip connection).