Plastic Cord Locks Cord locks are most often used in conjunction with parachute cord. You've seen them on backpacks, sweat pants and sweatshirts, and on drawstrings everywhere. Now we carry a wide variety of shapes and colors. We have barrel style, block style, ball style, and bowling pin style in stock. Assorted colors. Please send note of which style and color you would like, and we will let you know if it is stock or how long to order.