This is my 6920-EPR CK conversion kit upper half only I got last September, it had the original 13.5" Centurion Arms SMR M-LOK standard model rail (not the cheaper OEM model with less vent holes and QD sling mounts).
The new rail have two mounting fasteners instead of the older version with three mounting fasteners, also the markings are black color now, the older version had white markings.
I replaced the factory 13.5" handguard with a new Centurion 15" handguard I got last February, the swap was very easy just remove the two mounting screws then align the top rail and torque the mounting screws, done in a few minutes.
Here's my older made in 2019 6920-EPR CK conversion kit upper half only, with the standard model Centurion Arms 13.5" handguard, notice the three mounting fasteners and white markings, other features are the same as the new version.
I only have the upper half EPR to compare the old version and the new version, aside from the two differences of the fasteners and markings color they're mostly the same quality.
The Colt LE6920 marked M4 Carbine lower half was an older made in 2016 with Magpul MOE-K2 grip and B5 Systems Enhanced SOPMOD buttstock.