HEAVY DUTY HIGH QUALITY KEY CHAIN RINGS - Heat Treated and Lead Free -The benefits of heat treated steel are increased strength, hardness, toughness, and wear resistance. It should be a lot harder for you be able to bend it and break it. JUST UNDER ONE INCH - PERFECT SIZE at 15/16" (24mm) diameter, these split rings don't take up extra space and are perfect for Car Keys, House Keys, Organizing and Arts and Crafts BULK 100 PACK BLANKS FOR CRAFTING, LANYARD MAKING, LEATHER CRAFTS - The perfect addition to any maker's supply shop. Tons of uses. SUPER STRONG / SMOOTH ROUNDED SPIRAL EDGE- Custom made especially for Specialist ID. Be mindful of imitations out there of unknown origins. Our products are safe, strong, super high quality and lead free. STURDY AND DURABLE FOR HOME OFFICE & MAKING - Great for Car Dealerships, Landlords, Wood, Textile, and Metal Working and More! These amazing little key rings are super strong, super high quality, and are what we've been using as components in Specialist ID Products for years! The benefits of heat treated steel are increased strength, hardness, toughness, and wear resistance. Making them much harder to bend or break. This process basically alters the micro-structure of the steel by exposing the steel to high temperature for a certain period and then quenching it (rapidly cool). The product is nickel plated after the treatment.