The products from National Instruments (GPIB-USB-B or GPIB-USB-HS) and LeCroy (WS-GPIB) are USB host to GPIB device adapter. These would be used for instruments that have a GPIB interface with controllers that have a USB port. The TEK-USB-488 was designed for Tektronix instruments that have a USB device port with controllers that have a GPIB port.