Coil and straight hybrid performance. Compact lock uses a proprietary memory foam cable (birotation). Ordinary coiled cables may cause stretch due to over-pulling, but Q-BIRO memory cables have a characteristic that is not easy to stretch. This allows you to use the full length of the cable like a straight type, but it will fit into its original shape when stored. The tail is made with a metal ring that makes it easy to hold when locking, and can be double looped through the head.