Conversion : 1 inch = 25.4mm or 1mm = 0.0393 inch,1cm=10mm.Notice：Product selling points: 1. Easy to use. The hair is realistic, the is soft, not easy to break.Type:Straight wigMaterial:Synthetic Hair（high temperature silk）3. The colored hair is long enough that you can trim it to fit your hair length.size：18inch2. 100% Heat- synthetic fiber up to 180 degrees Celsius (360 degrees Fahrenheit), you can decorate it with a straight hair stick or a curling iron.（Note: curling method is different from human hair, please see the picture for details.）Please allow 1-3mm error due to manual measurement.5. Perfect to use for parties, cosplay, costume party, halloween or any casual events.Color: as the picture shows4. Natural black, can be dyed and bleached.Make you younger, active, attracted and elegant.Specification: 115g1x wig piece