How to identify an iSis or iSis 2 device by their serial number...numbers above 10000 are iSis 2 and below 10000 are 1st generation iSis devices. There was a running serial number change when X-Rite went from a four digit serial number (i.e., 003219, 001294, 002765) in the 1st Generation iSis devices to a five digit serial number (i.e., 010235, 010561) with the iSis 2. So...any iSis device that has a serial number above 10000 is an iSis 2. Please keep in mind that the label that has the serial number (on the bottom of the iSis device) will identify as an iSis or iSis 2 as well.