The Machine Weft is the finished look used for sew-ins.  This is the hair used for popular Weave Sew-in.
The Clip-In, on the other hand, is made from Machine weft but is pre-cut and Wig Clip attached to it.
The Clip-In is for temporary use, the Clips attached to the Clip-In is used as the anchor to attach it to your own hair.
The Clip-In Hair Extensions requires the wearer to have at least 4 inches of the natural hair for the best result.  Also, the Clip-In Hair Texture you intend to buy MUST match your natural hair or closer in texture hence you are mixing it with your natural hair.
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