Final answer:
Double notched thinning shears are used in hairdressing to remove bulk and blend layers in hair, achieving a textured look without changing the hairstyle's length.
Step-by-step explanation:
Double notched thinning shears are not related to needles of conifers, but rather they are a specialized tool used in hairdressing and cosmetology. These shears are specifically designed to remove bulk and blend layers in hair without altering the hairstyle's overall length. They are distinct from regular scissors as they have two jagged blades that help achieve a textured look by selectively thinning out sections of hair. The objective of using double notched thinning shears is to make the hair more manageable, reduce the volume in thick hair, or create a seamless blend between different lengths of hair within a haircut.