Our Swivel Snap Hooks are zinc alloy material made of, lead-free environmentally friendly health, for quality and safe for use. The key hook is 1 1/2 inches in length with a 3/4” inside width D ring, They are small size to fit for small sewing projects. Swivel Snap Hooks are great for making , purse, backpacks, handmade dog collars, luggage straps and so on.endless creative possibilities with these key chain hooks, make you a star creator.