https://www.techtimes.com/articles/...5g-smartphones-what-difference-x55-modems.htm
“The X60 is a subtle leap from the X55 as it promises tons of systems upgrade that will improve its integration with future smartphones. The predecessors X50 and X55 brought the world its first look at better carrier connectivity with the first-generation 5G technology for the whole world...
The X60 brings improvement to a smartphone's better battery life, connection speeds, and overall performance. Qualcomm boasts of the new sub-6GHz and mmWave aggregation that is purposely combined to give a more reliable connection speed using the 5G.
Additionally, the 5nm processing node packs higher power efficiency while having a smaller footprint on the technology. The sub-carrier aggregation of the 6GHz configuration also helps networks "maximize their spectrum resources" for coverage and peak speeds.
The 5G SA connections that would be compatible with Qualcomm's X60 also helps networks to double peak speeds, something that the X55 did not have during its release. Moreover, X60's antenna module, QTM535, would be smaller than the past versions to offer a "sleek" mmWave smartphone design.”