PROX-USB. The PROX-USB Desktop Reader from Videx is a USB desktop proximity enrolment reader for EM, Mifare & HID fobs and cards, designed for use with the Portal Plus access conrol system. The desktop proximity readers connect to a PC running the PROS CS Portal Plus software and allows the enrolment of fobs or cards (EM, Mifare & HID formats) while the desktop fingerprint readers allows the enrolment of fingerprint templates.. Portal Plus desktop proximity reader. For EM, Mifare & HID fobs and cards. USB connection.