Years ago I got back “into” tighty whities that had double and even front-layers of fabric in the seat when I found out about Tiger Underwear. As an avid collector of all kinds of underwear…especially white briefs…I found these on-line, I believe on Amazon but I wouldn’t swear to it.
I remember getting two of them. They are Bell’s double-seat tighty whities; the whole seat, from side seam to side seam is two layers of 100% (as is the rest of the underwear) cotton…except for the waistband, of course.
The pair I’m wearing in this set of photos is “made to fit a 85 cm” waist which is roughly 34″…they fit just right!