The Bozily VPRO-X1 Rangefinder is the older version, while the Bozily VPRO-X2 is a newer variant that offers you a greater distance coverage of 1500yards. The former only offered 1000yards. In addition, there are several other technological advancements in the Bozily VPRO-X2, including an upgraded scan mode too. So, basically, the Bozily VPRO-X2 rangefinder is the upgraded version.