Apex Mass Flow Controllers for vacuum and pressure applications combine flexibility with outstanding accuracy. Our mass flow controllers are multi-gas capable with a flexibility to choose from a list of up to 130 on-board gases. We offer the option to choose your input and output voltage along with the ability to use RS232 data communications. Using the optional BB9-USB Communications Box, our Apex Mass Flow Controllers can control up to 27 Apex devices through one RS232 port, providing your set-up the ultimate flexibility.