Yeastar EX08 4-Slot Expansion Board Yeastar EX08 4-Slot Expansion BoardYeastar EX08 expansion board supports S100 and S300 VoIP PBX, and has 4 onboard module slots and 8 interfaces on the panel. Expansion Board for Yeastar S100 and S300 systems Supports up to 4 optional modules/8 ports, including O2, S2, B2, GSM, UMTS, and CDMA modules Add up to 2 expansion cards to S100 and 3 to the S300.
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