The Fontaine Fifth Wheel 6NWB Fifth Wheel Assembly features a lightweight 6000 No-Slack top plate mounted to a lightweight Fontaine NWB sliding bracket, resulting in a 60 lbs lighter weight, according to the company. The 6NWB offers No-Slack technology, so the lock automatically self-adjusts to trailer kingpin variances to help provide a smoother ride, lower maintenance costs and lengthen component life. The 6NWB is rated at 50,000 lbs vertical load with a drawbar pull rating of 150,000 lbs.