Amazon.com: Snap Extender Leather Choker Collar Bracelet Necklace Extension 2" to 4" Inch (SNAP SM-7MM) : Clothing, Shoes & Jewelry
Necklace, choker, nylon and imitation rhodium-finished steel, black, 9mm wide, 12-1/2 inches with 2-inch extender chain and lobster claw clasp. Sold per pkg of 2. - Fire Mountain Gems and Beads
Additional Option: Pink and Black Leather Choker Extender - Etsy