To meet all requirements and also to address customers who do not like long hair extensions, we also included extensions in 35 cm. It is certainly a matter of strands with keratin bonds, which are to attached by hair connector iron. These pre-bonded extensions are also suitable for working with an ultrasonic device. The strands are each 1 gram-heavy, so it is guaranteed that you need less strands than for example with 0.7 gram strands. As a rule, approximately 75 of these strands are required for a complete hair extension. With very dense hair we recommend 150 strands for a nice result.