I think as long as they're smooth and you don't pull your hair too tight, those are fine. FYI you can make them yourself by buying elastic by the yard at your sewing store!
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3b, fine, medium density, normal porosity
Wash: Phytolisse and Shea 10-in-1
Rinse-out: CJ Deep Fix, Phytolisse, Shea 10-in-1
DT: CJ CCCC Lite
Leave-in: Phytokeratine, CCCCL
Styling: Phyto hair curling stuff or Deva Coconut Supercream (which may turn out to be a HG for me!)