100% human nail tip hair extensions boast the following features:
Sold in bundles of 25 strands (0.5 gram/per strand) Cuticle Correct & Silky Straight.
These are pre bonded extensions which come with the nail tip keratin bonds already attached. The glue used is made of high quality keratin. The keratin bonds are applied using a fusion applicator, which uses heat to melts the bonds. The quality of the hair is called Chinese Remy which means that they are tangle-free. The hair strands remain straight and parallel in the same direction. They can last for 2/3 months when proper care is taken with them. You can wash them, curl them and also straighten as per your requirements.
For full head, 150 to 200 strands would be sufficient and for half head 75 to 100 strands would be sufficient from the 0.5g range. These are approximate values, the actual value depends on the thickness of your hair and the volume that you are willing to achieve.