so i forgot to say something earlier when the whole battery adjustment length issue was being addressed, but i'd thought i'd share anyway. I use the "Vitolo Method" as well for adjustment and found it works, but in regards to battery sticking out the top i have a few points to make. firstly, i instinctively wanted to have the battery stick out a mil or so extra to make sure i had a good connection when i got this. after my single top started going blinky i was worried it was the battery length so i started kicking it out a few millimeters more. when i realized it was just the top after switching over to my double top i stopped doing that. then i got my hammer top (which i love, btw. very solid. much better thread setting, and now i have a two-tone w/ an on/off button for low voltage) which flashes like the v2 when it makes contact, which it does well before threads are tightened anywhere near all the way, even when the battery is barely flush. just an fyi. it's is unnecessary to crank the batteries into the top. my 2 cents