  The Fermi Large Area Telescope (Fermi-LAT) 3FHL catalog is the latest catalog
of >10 GeV sources and will remain an important resource for the high-energy
community for the foreseeable future. Therefore, it is crucial that this
catalog is made complete by providing associations for most sources. In this
paper, we present the results of the X-ray analysis of 38 3FHL sources. We
found a single bright X-ray source in 20 fields, two sources each in two fields
and none for the remaining 16. The analysis of the properties of the 22 3FHL
fields with X-ray sources led us to believe that most (19/22) are of
extra-galactic origin. A machine-learning algorithm was used to determine the
source type and we find that 15 potential blazars are likely BL Lacertae
objects (BL Lacs). This is consistent with the fact that BL Lacs are by far the
most numerous population detected above >10 GeV in the 3FHL.
