American Power Conversion today announced the Back-UPS ES 350 and ES 500 uninterruptible power supplies (UPS). The newly designed units offer USB connectivity for Mac OS X to provide file-saving and auto-shutdown capability, six outlets (three battery plus surge, and three surge-only), and fax/modem/ DSL surge protection. The Back-UPS ES 350 (US$39.99) provides 19 minutes of runtime after a power outage, and the Back-UPS ES 500 ($59.99) will provide up to 40 minutes of runtime.