An arresting device used in a cot fastening system for an ambulance is disclosed. The arresting device includes an extension beam providing a bolt pattern, and a pair of antler brackets each having a mounting hook portion. The pair of antler brackets is mounted to the extension beam. The present invention may be used with a plurality of prior art cots, without requiring modifications or installation changes to the ambulance or the cot fastening system to which the arresting device is a part thereof.