a flexible tie including a head having a first cross - sectional geometry and a tail extending from the head in a longitudinal direction and having a second cross - sectional geometry different from the first cross - sectional geometry . the tie includes a lock disposed on the head and including a passage configured to receive the tail and a plurality of barbs disposed on the tail and configured to pass through the passage in the lock in a first direction , and configured to be restricted from retreating through the passage in a second direction opposite to the first direction . the tie also includes a tail break - point disposed on the tail and including a first cross - sectional area , as viewed along the longitudinal direction , smaller than any other cross - sectional area of the tail as viewed along the longitudinal direction . in some configurations , the tie includes a visual indicator in the head .