Dental Orthodontic Braces Rubber Chains,Orthodontic Rubber Power Chains for Braces. A necessary and useful tools for orthodontic treatment,a good helper for shrinking the teeth gap during orthodontic treatment. Color:As Main Images Show Size:Long(4.0mm),Open(3.5mm),Closed(2.8mm) is shown as the distance between the two rubber bands.Please be sure to read the specifications and purchase the size you need. Total length:15 FT per roll Packing include:Orthodontic Rubber Chain 1 roll.