26G 360 Spial Cog is a uni-directional barbed thread. Doctor gently presses the skin in direction of desired lift and then inserts 26G 360 Spiral Cog beneath skin surface for firm fixation. PLLA petit is used for sagging skin in narrow area such as crow’s feet, eye brows, nasolabial fold. It attaches the skin tissue and pulls back to lift tightly.