Hair Serum is a liquid based treatment usually formulated using 

silicones that provide a protective layer over the hair fibre,

assisting in smoothing frizz.

This smooth layer then reflects the light,which is how serum 

gives your hair a shiny,not greasy,finish.

Hair Serum is normally applied onto wet or towel-dried hair 

after shampooing and conditioning.

The top best hair serums in India are- Streax Pro Hair Serum Vita 

Gloss,L'Oreal Paris smooth intense serum,Livon Serum,Urbangabru Hair

Serum,etc.