|$29.95 through AAFES|
The question may come up before you leave for BMT about what to do with your wedding ring. If you have a beautiful, expensive wedding ring, leave it at home. The training environment is not conducive for keeping your valuables safe and unharmed.
The females in my flight that brought their wedding rings to BMT ended up keeping them in their security drawers and didn't wear them until graduation weekend. While that's an option, I probably wouldn't want to run the risk of having something happen to it in there, if you were careless about leaving your drawer unlocked.
One of my flight members wore her rings to PT one morning, and ended up taking them off and putting them into the tiny pocket on her PT shorts. Do I even need to tell you what happened next? She lost them. Fortunately, our MTIs were nice enough to allow her and another trainee to go look for them, and they were eventually found. Your MTI may not be so nice and you may not be so lucky. If she would've lost those rings in the sand pits, she could've kissed them goodbye.
Many opted to have their spouses bring them their wedding rings during graduation weekend. When we saw our families on Thursday, they would be able to get their rings, and therefore have them for Friday's Parade and the rest of the weekend, not to mention tech school. This is a much better option to ensure that your ring is safe.
If you want to wear some sort of ring while you're down there, I would encourage you to buy a cheap band. The above pictured ring is sold through AAFES for $29.95. You can get them in Tungsten or Titanium, they are unisex in desire, and they are very comfortable. I opted for one of these before I left for BMT and I actually wear it more than my "real" ring now.
[Sadly, I managed to misplace this ring yesterday, and it's weighing heavily on my mind right now. That ring has been through so much with me! Keep your fingers crossed that I stumble over it tonight.]