Most extension education teaches speed and volume. The result: tension-heavy installs that stress the scalp, compromise hair health, and don't last. The 9 Stitch™ Tri-Lock Method takes a different approach — precision tension engineering built on a crisscrossed triangle anchor system that distributes weight evenly across the scalp. The result is a softer, longer-lasting, more comfortable install. And maintenance requires no stitch removal — a major time and comfort advantage for you and your clients.