Patented micro-spiral grooves to remove lice and eggs. Please be aware if it doesn’t have 'Nitty Gritty NitFree’ ENGRAVED on the handle of the comb, it is NOT A GENUINE NITTY GRITTY COMB.One comb treats the whole familyContains no chemicals so safe for all agesRemoves nits AND eggs quickly in one goTo get the very best results, use with Nitty Gritty Head Lice Solution, but can be used with ordinary hair conditioner or other head lice treatment