These are
wefts
made manually using 8 threads to weave the hair in a particular pattern
to make the weft. Usually hand tied wefts are small in size and allows
the hair to hold tighter. A machine stitch is run on the weft again to
make it stronger. It is advised not to cut the weft. It will loosen and
shed. However, if you intend to cut the hand-tied wefts, please tie off
the cut ends or reinforce with glue to ensure that the hair will not
untangle. Because the wefts are made by hand there is greater control
over ensuring stability of the hair extension.
On an average a skilled person can weave up to a maximum of 3 - 4
pieces per day. That is, 300 to 400 grams of hair can be woven per day.
It needs enormous manual skills and training to weave continuously.