Portable X-ray inspection systems are frequently the first technology used by the authorities to assess the potential threat from a suspect device and their ability to generate an image of the device has allowed both terrorist incidents and false alarms to be avoided. A portable X-ray system consists of an X-ray generator, an X-ray detector panel and a user terminal, typically a PC or tablet computer. Important performance parameters include X-ray penetration, good image resolution, and more recently the ability to discriminate between materials. Our proposal is to utilise the IBEX materials classification technology, which uses a Multi Absorption Plate (MAP) and advanced software algorithms to create materials discrimination from a conventional amorphous silicon detector with a single energy scan. The enhanced capabilities of the proposed system are expected to lead to higher detection rates of small threat objects, and greater discrimination of organic-based materials such as homemade explosives and biological threats