Which as the name suggests is likely to be a «Pro» version of the standard ZenFone 4, where among other things, will come with upgraded specs compared to the standard ZenFone 4. (androidheadlines.com)
Nor do they substantially upgrade the specs of the original X9 / X9 Plus duo. (pocketnow.com)
Details on the device are still light, but it'll reportedly have a bigger screen and upgraded specs compared to the original Revvl. (tmonews.com)