Knitted Retraction Cord, Non-Impregnated. Unmedicated 100% pure cotton retraction cord. Knitted into thousands of tiny interlocking loops. Unique, knitted cord gently expands after packing to help aid in retraction. Knittrax knitted cord is ideal for creating full exposure of the margin which is the foundation for success in both conventional and digital dentistry. Available in Sizes 000, 00, 0, 1, 2