Mediant 1000B with 4 Spans, with Dual Power SupplyIncludes Mediant 1000B chassis, 1 Active/Standby pairs of GE interfaces, one module of 4 E1/T1 spans, single AC power supply and fans. Chassis can be expanded with any Mediant 1000 Voice modules such as FXS/FXO/BRI or T1/E1. Order M1KB-SWX module for additional 2 pairs of Active/Standby GE interfaces.One Year Manufacturer's Warranty - Support and Installation services are offered at an additional cost. See technical support options listed above.