Help identify size of prefolds & cover brand

[bostonsmama]

Help me identify the size of some prefolds I was given. I received a box of 3 dozen Indian cotton prefolds and some nonbranded covers. The woman didn't say where she got them, but she said they weren't small enough for her super skinny babies. She gave me 3 Thirsties covers in XS, which the PFs fit in perfectly w/out hanging out, and 3 other covers that have no labeling, are white, not lined w/ PUL, almost a thin neoprene/stretch poly with aplica/velcro closures. She stopped using these almost 2 years ago, so she doesn't really remember the details (where she got them, what size was called). She gave up CDing after too many blowouts from PFs & covers.

The PFs are unbleached, have white top stitching, and measure on average 10.5" x 12-12.5" after her multiple washings and little use. They're in great condition, but I'm having a hard time figuring out how useful they'll be to me since they're SO small. They're smaller than GMD's description of newborn PFs (11.5x12), and they look a LOT like GMD's premie PFs, although they're bigger than 11x9. They also don't look like 2-6-2 layering.

I'm trying to build my stash, and I'm just wondering how long these teeny tiny PFs will last me (GMD's NB PFs say only to about 6 weeks or 5-10lbs). Should I think of these as premies and get NB also, or should I just get some size Small (yellow) from GMD and see if she transitions straight from these to Smalls?

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