Refurbished Rheodyne MXT715-000 valve. The MXT715-000 is an Ultralife 2-position, 6-port motorized valve with patented MBB “Make-Before-Break” architecture. The MBB design insures that flow is not interrupted when the injector is switched between LOAD and INJECT when a loop is installed between ports 1 and 4. The small compact stand-alone unit is typically used as a switching and/or injection valve. May be purchased individually or with the Shimadzu Prominence HPLC. Please contact us for complete Rheodyne valve details.