The IA-3133L-U is a USB 32 Relays dual pole multiplexer board with 2 out of 64 selection ability, in 32 states. Its onboard firmware ensures a single relay activation in a `break before make` sequence. Other family members, as the IA-3133-U2i, can better serve as 2 to 64 Channels, with the ability to operate more than a single relay at a time. The IA-3133L-U is both powered and controlled by its USB port, with an onboard watchdog secured operation. The IA-3133L-U is Series-3000 compatible, with the same software support including easy operation utilities and open source samples.