The three main layers of the hair shaft.
Cortex
Cuticle
Medulla
Apex
Scale Overlap
Defense
Attached
Health
Protein
Medulla
Cortex
Cuticle
Elasticity
Natural color
Unique protein
All of the above
Cuticle
Cortex
Medulla
Alkaline
Medulla
Protein
Chemicals
All Of the Above.
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