... use.with CE and UL or ROHS certification. Led Moving DisplayFeathersDisplay Element f 5mm (default), f 3.75mm or ... f 3.0mm LED dot matrixes or LED lamps for ... , Amber, Blue, Pure Green, or White etc.Average LED lifetime 100,000 hoursPC Communication RS232, RS422, Email, Modem ... convertor, Modem, GSM Modem, Ethernet adapter Led Moving Display