Silicone-Lined Micro Rings Are Made Of Aluminum Metal. Interior Of The Ring Is Cushioned Silicone Lining, Which Will Protect Your Hair From Being Damaged. It Holds Human Hair Very Tightly After Pinched And It Will Not Easily Get Slide When Wearing. 1. It Can Hold Tightly And Will Not Slip Easily After It Clamps To The Hair. 2. Made Of Premium Silicone Material, The Silicone Hair Extension Ring Can Be Applied To The Hair Safely With No Damage To The Hair. 3. The Hair Ring Surface Is Processed By High-Quality Baking Varnish, So The Lacquer Surface Is Not Easy To Fall Off, And The Using Time Is Long. 4. The Silicone Button Cut Is Smooth, Burr-Free, And Unhooked. Product Details Material: Premium Light Aluminum Silicone Size: 5.0Mm (Outside Diameter) X 3.0Mm (Inside Diameter) X 3.0Mm (Length) Color: Dark Brown Quantity: 1X Bottle Of 1000 Pcs.