Amazon.com: Luanxu 4.5 mm Stainless Steel Bead Chain for Blinds & Shades with 5 Connectors, Fix or Replace for Broken Roller Blind Curtain Chain, Great Pulling Force & Rustproof (#10, 3 Meters) :
Size #10 Continuous Plastic Bead Chain Loop for Roller Shades – Fix My Blinds
Size #10 Plastic Bead Chain for Roller Shades & Vertical Blinds - 12mm – Fix My Blinds