Check the listing for details. NEW Celerity/Unit UFC-1661 SiH2Cl2 500sccm Mass Flow Controller ASM 54-123389A31. Condition: New – Open box. Listed at 954.10 USD. NEW Celerity/Unit UFC-1661 SiH2Cl2 500sccm Mass Flow Controller (MFC), ASM PN: 54-123389A31 Comes with what you see in the pictures. If you don't see it, you probably wont get it. Specifications are from Advanced Energy and may vary slightly due to upgrades, options, or revisions this unit may or may not have. This part is new, old stock from ASM. The package may have been opened and re-sealed to recalibrate the units so that ASM could ship them when a customer ordered them. The calibration is past due however. ASM Information: Part Number: 54-123389A31 Description: SU-BY 1011-207-01-FC-UNIT 1661-SIH2CL2-5 The ASM Tag Reads: Part Number: 54-123389A31 Description: FC-UNIT 1661-SIH2CL2-500 SCCM NC @10 The Box and Unit's Tag Reads: Model Number: UFC-1661 Part Number: C1661AS-0067500C-4RHOVVMFE-XXXX-CSX-10E Flow Range: 500 cc Gas: SiH2Cl2 Valve: NC Attitude: HOV Seal: MF Response: S Exhaust: V Connector: CrdEdg Option: AS PID FW: 1.02 CSR: XXXX Reference: 0C, 760T Breakdown by Part Number: Gas Flow Controller Digital, Metal Seal Auto Shut-Off (Std) 5 Second Linear Soft Start 500 sccm, SiH2Cl2 1/4" VCR (Std) Horizontal or Vertical Mounting Position (Std) Vacuum Downstream Pressure Metal O-Ring / Kel F Seat Card Edge Connector, 0 - 5 VDC Normally Closed Solenoid Valve (Std.) Valve Downstream (Std) Auto-Zero Disabled 10 µ in Ra For Domestic Customers: Packaging, handling, and order processing included in shipping in all domestic shipments as quoted by the shipping calculator. For International Customers there is a $15.00 minimum for packaging, handling, and order processing. International shipping to be determined by destination. Prior to shipment I will need to know the following information (filled out on a form that I will send you) for International Customers or Packages/Freight being Forwarded internationally. International customers may also be subject to a freight forwarder form if applicable.: (1) Are you the end-user of this item? (2) If you are not the ultimate end-user of the item, please state the ultimate end user's name. (3) What is the ultimate country destination? 05/02/12