15
Do you wear Calvin Klein underwear?
(discuss.online)
Coming from this post, I made an online Moldovan friend & he's asking me about life in the US :):
I for one just wear whatever Costco has for reasonable prices
Nah.
In general, Hanes or Fruit of the Loom would be the most common brand. I haven't seen numbers in ages, and have no interest in looking them up, but they used to be the top two (or bottom two, depending on if you want wordplay or not).