BLACK Bright Anodized Aluminum permanently colored (not a paint or cheap coating)! 500 High Quality 1/8" ID 20 gauge SAW CUT Aluminum Jump Rings, clean saw cut for no burrs! 1/8 is the Inside Diameter of the ring, 20 gauge or .036" aluminum is the width of the wire used! These are saw cut rings for a perfect circle when closed making the seam virtually invisible!