Material: Carbon Steel Surface: Zine Plated Which Prevent Rust And Durable In Use. . Assembly: The Nuts Are Mounted In The Component Previously Drilled With A Hammer. Thanks to The Four Claws, The Nut Is Fixed Deeper In The Material to Be Worked. This Gives Life to An Additional And Safe Screw Connection. . Scope of Delivery: M3/M4/M5/M6/M8, A 90Pcs Heilwiy Kit to Meet Your Different Needs. Ideal for Professionals, Diyers, Carpenters, Construction Workers, Plumbers, Etc. . Easy to Use: The Four Claw T-Nut Kit Is Equipped With A High Quality Transparent Storage Box That Can Be Divided Into Sections for Easy Sorting And Use. You DonT Have to Worry About Getting Them Confused Or Losing Them. . Wide Range of Applications: T-Nuts Are Mainly Used for Metal And Wood. for The Assembly of Furniture, Jigs, Protections, Etc. .