Dust cover?

It is not required, as the connector is waterproof.  But there are a variety of cheap choices on Amazon that do help keep gunk and crud out; I use them myself. 

I just make sure I wipe down the connectors after I workout to keep them dry and dirt free.  I also did buy some of those cheap covers in from Aliexpress but I have not received them yet.

Wow I didn't even know those existed, never would've even thought to look for them. Pretty cool! Just ordered a 12-pack of them for $6 on amazon.

My Vivoactive has the same connector as the Fenix, and I've never had an issue with it getting dirty, but the exposed contacts still always bothered me, just from an OCD point of view.

hi,

I highly recommend those silicone caps you can find on net.

my 5x+ has corrosion signs on the contacts, mostly on the right side one.

yes, I've tried to keep it clean, to rinse and dry after workouts, after a swim,  and for sure before connecting the cable.

still happened.

since, I have the same feeling as @9391586 about those naked contacts.

when I bought 6X PS I purchased also the caps.

are tight, I do not see moisture after immersing in water.

to me is a big plus for under a buck.

just me,

robert