Fabulength halo hair extensions by Revlon are 2 x 18" long heat friendly extensions that provide length, volume and can give you additional colour dimensions... all on an invisible crown wire. There are no fiddly clips, so simply lift up your hair at the crown area and put the stretchy, silicone thread over your crown. This very strong thread will then settle naturally into it's own position. There are two extensions within a pack, so you can either go for subtle volume, or add both of them for more impact.