The new DixiLoc feature allows these binders to be locked in the closed position with any 7/16" lynch pin or standard padlock (not included). A padlock is recommended to secure cargo from theft. The physical block prevents the binder from opening regardless of movement or slack in the binder chain. The binder has a safe working load of 5400 lbs and is designed for use with 3/8" G43 and 5/16" G70 chain. Each unit is individually proof tested and meets all DOT regulations and CVSA guidelines.