Comb used as hair fastener

Comb used as hair fastener, Makers Pictured,  photographs by Amy Marjoram

Roadside town between Muong Lay and Dien Bien Phu, Vietnam.

I believe these women may be ethnically Black Hmong, many Black Hmong women wear there hair combed up and held either with metal combs or modern plastic combs.  I previously only associated these archetypal plastic combs with the act of combing, not for holding hair in place, which now seems like an obvious usage.