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: Up in the air right now; Phytolisse and Shea 10-in-1 not working amazingly
Rinse-out: CJ Deep Fix, Phytolisse, Shea 10-in-1
DT: CJ CCCC Lite, Phyto 7
Leave-in: Phytokeratine, CCCCL
Styling: Phyto hair curling stuff