【Premium Durable Material】Crafted from heavy-duty nickel-plated iron with stainless steel-grade plating, these large safety pins resist rust, bending, and breakage. Sharp tips ensure effortless penetration while maintaining long-lasting durability for repeated use. 【Secure Safety Lock Design】Each heavy-duty safety pin features a reinforced locking clasp that fully encases the sharp tip, preventing accidental openings and ensuring maximum protection during use. 【Smooth & Sharp Heavy-Duty Penetration】Polished edges prevent fabric snagging, while precision-crafted tips easily pierce thick materials like denim, leather, or multiple fabric layers without damage. 【Multi-Purpose Versatility】Ideal for kilts, crafts, quilting, clothing repairs, blankets, upholstery, and DIY projects. Doubles as sturdy organizers for documents, photos, or industrial tagging with safety-lock reliability. 【36-Piece Multi-Size Kit】Includes 12pcs 5cm×1.5mm, 12pcs 6cm×1.5mm, and 12pcs 8cm×1.8mm nickel-colored pins. Three sizes tackle tasks from delicate fabrics to extra-heavy materials.