I can't recall specifically but it was while I was testing the current. I removed the tube and only had the battery carrier pressed up against the base of the head. I did see some small sparks but nothing unusual, however, after a few times of this it didn't register any reading on my DMM so that's when I found out the carrier had protection built-in.
This was right after I received the V60C and since I needed to get the review completed at the time, I created a "bridge" with a paper clip to connect the positive tip from the first battery (in series) with the central "leg" of the carrier that routes the positive path.
There are additional details I need to add to this review which will include the battery carrier. Should have that up later tonight.
I purchased some off white plastic hole plugs off Ebay that fit perfectly - except for the prongs that were a bit too deep/long. I have a dremel tool and it took just a few minutes to grind them down for about an eighth of an inch.
UPDATE: The fit wasn’t as tight as I hoped - the plug fell out after a little jostling of the light. I tried to expand the prongs to make it fit better but that didn’t work. If they made these plugs in 11mm that would be perfect, but I can’t find them anywhere…
I found black 44mm plastic camera lens cap covers on Ebay that work perfectly as a tailcap cover - nice, snug fit. Even the lanyard holes are left unobstructed! How does five pieces for $5.45 shipped sound? Pics: