Unbreakable plastic comb works on coarse or fine hair. Removes lice and eggs. The lice comb is used after someone with a lice infestation has had a treatment with a lice killing shampoo. To guarantee total removal of lice and prevent reinfestation, the lice comb is used to remove nits from the hair. These nits may still harbor living lice embryos, even after treatment with special lice killing shampoo.