Hello,
Exactly which USB device are you referring to? Is the device a NI product?
The Product ID for National Instruments DAQPad-6020E is 0x12C0. The USB vendor ID is 0x3923. This is a 16-bit hexadecimal number(1093) (that is decimal 4243).
Also, here's a document on our website that will help you in configuring NI-VISA to control your USB device:
http://zone.ni.com/devzone/conceptd.nsf/webmain/6792BAB18242082786256DD7006B6416?opendocument
Swapnil P.
National Instruments Engineer