O's Guide to Hair Extensions

Who They're Good For: Someone who wants longer or thicker hair temporarily.

Who Should Avoid Them: Anyone with fine hair that can't hide the clips.

What They Are: Clip-in extensions range from a one-inch piece with one clip to a weft that runs from ear to ear with three to five clips. They're made with human or synthetic hair and come wavy or straight and in a wide range of shades. Clip them underneath the top layer of your hair to conceal the attachment.
How Long the Process Takes: Five to ten minutes.

Maintenance: You can shampoo and restyle them.

How Long They Last: EClip in and remove as often as you like (but don't shower or sleep with them in). Quality extensions can be reused forever.

Price: At a salon, you'll pay $500 to $1,000 for eight pieces (which includes a consultation, fitting, and lesson on attaching them). Some salons offer rentals: At Warren-Tricomi Salons in New York City, you can rent clip-in extensions for a day for $100. Or you can buy them and put them in yourself; two popular, natural-looking options are HairDo 5 Piece Clip-In Ultra Invisible 16 Extensions ($49; QVC.com ) and Ted Gibson Clip-In Extension Systems ($150; ShopNBC.com ), which are made of a new protein-based synthetic hair that can withstand hot rollers, a curling iron, or a straightener.

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