NiSi UHD UV Protective Filter for Fujifilm X100/X100S/X100F/X100T/X100V (Silver)

This one's great. It's 2 in 1 lens hood and UV filter and fits the original lens cap perfectly. https://www.amazon.com/NiSi-Filter-FUJIFILM-X100V-X100F/dp/B0869952VJ