Enables simultaneous traffic on both DS3/E3 ports, effectively doubling the bandwidth through the converter. This option is delivered in the form of a password file which is uploaded to a model 1x-... device and which converts it to a 2x-...device. Not necessary if purchasing a model 2x-... device initially. Availability: Usually ships the next business day DualUpgrade_1x_to_2x$1,000.00 Copyright (c) 2011, E3Switch LLC, all rights reserved.