Well, I took my brand new P320RX to the farm for some shooting. Tightened the battery cap with the plastic screwdriver (before reading, here, that such was a problem). Anyway, you guessed it. Somewhere through the 2nd mag, the cap came loose and fell into the weeds. After 60 minutes of searching on my knees (not much fun for a Medicare guy), I gave up trying to find the battery cap. Figured somebody might sell a replacement cap but am having no luck in locating them on the web. Could one of you kind (and search-proficient) souls point me in the right direction so I can buy a replacement (I promise, I'll tighten this one with a real screwdriver). Many thanks in advance

You are going to have to call SIG on that one as I seriously doubt anyone other than them will have availability for such an item, sorry.

Sig should just send or sell you one. The Romeo sights were originally made by another company but I think. though not sure that Sig now makes them so they should have parts. If the CS rep you get says it isn't a warranty issue and won't help, hang up wait a day and call back to get someone else.

Well, Sig wouldn't sell me a new battery cap. But they were more than happy to GIVE me one even though I was the one who didn't torque down the cap properly. Paul in customer service was absolutely awesome. I guess this just reinforces my decisions (7 of them) to buy Sigs in the past. "Customer service" for most companies is a real misnomer these days...but not with this company (and no, I don't work for them; I'm an ambulance-chasing, blood-sucking lawyer)

How dare they treat you in that manner when this is clearly your fault.

May I make the following suggestion. When I got my first Rx I had the same issue with the cap loosening up until I torqued it down properly. After I got the cap torqued down I took a silver paint marker and drew a line across the cap onto the body of the optic so that I had a witness mark that would indicate any movement of the cap. The cap hasn't moved since but I also have the piece of mind knowing it hasn't moved.

ETA: This isn't mine but it would look something like this.

Excellent idea (much better than buying a mini-torque wrench)!