The SST® is a trailer mounted attenuator for use on stationary or moving shadow support vehicles. It is tested to NCHRP Report 350 Test Level 3. The system is comprised of two lightweight aluminum cartridges contained in a steel support frame, heavy duty Torflex® axle and wheels, with anti-rotational dampeners which lock upon impact. The SST® is designed to help absorb rear-end impacts at speeds up to 62 mph (100 km/h) when impacted within NCHRP Report 350 crash test standards.


  • Trailer system for more efficient deployment and truck fleet utilization.
  • Anti-rotational dampeners are designed to help minimize rotation of unit when impacted within NCHRP Report 350 crash test standards.
  • Heavy duty Torflex® axle and wheels.
  • Arrow board mounting systems available.
  • Designed to help minimize damage from low-speed nuisance hits up to 6 mph (10 km/h).
  • Potentially reusable steel frame after an impact within NCHRP Report 350 crash test standards.*


*After an impact, the product must be inspected and evaluated per the direction of the specifying roadway authority. The ultimate decision on reusability rests with the specifying roadway authority and/or state DOT.

Assembly & Maintenance

  • Attaches to a standard minimum 20 ton pintle hook with additional mounting brackets for the anti-rotational dampeners.





  • 18’ 11” (5.77 m) Length
  • 7’ 9″ (2.36 m) Width
  • 3’ 9″ (1.14 m) Height
  • 2,606 lbs. (1,182 kg)
  • 9,920 lbs. (4,500 kg) Minimum Support Vehicle Weight

Product Images

Product Documents


PI Sheet


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