Stalwart® Post & Rail  Anti-Ram Crash Barrier

Stalwart® Post & Rail  Anti-Ram Crash Barrier

The Stalwart anti-ram barrier is a standalone crash barrier. The post and rail fence system is the most economical passive perimeter barrier system available on the market. The Stalwart standalone design when installed adjacent to an existing perimeter fence, transforms the perimeter into a secure anti-crash perimeter system.


There are multiple facilities that are required to increase perimeter security beyond their current attempts with high security ornamental fence, welded wire, expanded metal, or chain link fences. These new requirements for increased security are to protect areas at risk from vehicle threat. The Stalwart anti-ram barrier system is the best option for increasing security with existing pedestrian fence or as a standalone barrier. The Stalwart fence framework provides a platform to incorporate various security peripherals required on high security perimeter designs.

The components that define the Stalwart fence framework are used to carry the anti-ram cable transforming the system into a crash fence system. The Stalwart anti-crash barrier has been engineered and tested in compliance with current ASTM F2656-07 (Standard Test Method for Vehicle Crash Testing of Perimeter Barriers), and meets the demand for multiple vehicle threats.


The Stalwart fence framework provides a platform to incorporate various security peripherals required on high security perimeter designs.

Integrated Design

The unique shape of this product's rail enables its security fence designs to incorporate all forms of physical security protection and detection equipment into a single perimeter solution.

Use the Impasse rail as a raceway for electrical conduits.

Impasse rail as raceway for wiring

There are many costly elements to consider when securing an asset;  lighting, access control wiring, intrusion detection sensor wiring, communication fiber, and electrical wiring are several of the elements that are required in today’s perimeter security systems.  The Impasse rail is designed to house all peripherals required to complete a perimeter security system without the outrageous expense of trenching and boring typically used in these applications.

Use the Impasse rail to covertly secure IDS to the security fence.

Impasse rail as raceway for wiring

The Impasse rail is a one-of-a-kind design which can easily incorporate any intrusion detection sensor.  The unique shape of the Impasse rail covertly houses IDS cables to delay, deny, deter and detect unwanted intruders.  The secure IDS attachment harnessed with the rigid construction of an Ameristar fence system simultaneously provides a high probability of detection and low rate of nuisance and false alarms. 

Use the Impasse rail to carry communications along the perimeter

Impasse rail as raceway for wiring.
The Impasse rail can also easily incorporate wiring for video, CCTV and other communications. The Impasse II fence sytstem easliy provides a high probability of detection. 

Use the Impasse rail to connect access controls at each entry.

Impasse Rail with Access Control

Access control has become a very important element in securing drive entry and pedestrian entry at the perimeter.  The Impasse rail enables access control wiring to be easily added from one entry control point to the next without spending project funds on a patchwork design using trenching and boring.

Use the Impasse rail to conceal crash barrier components.

Impasse with Anti-Ram Barrier

The Impasse rail is designed to house the cable of the Stalwart anti-ram barrier system.  The typical 4 and 5 rail configurations are arranged to meet the specifications of the Stalwart anti-ram barrier.  When design elements are taken into consideration the security fence can be installed so that the Stalwart anti-ram barrier can be incorporated into the fence at a later date if required.

The ASTM F2656 standard recognizes a 15,000 lbs. truck traveling at 50 miles per hour as an "M50." The "P1" designation represents a penetration of less than 3 feet within the perimeter. ASTM ratings were created to replace those determined by the U.S. Department of State. In the previous ratings system developed by the U.S. Department of State, a "K12" barrier was equivalent to the current M50.

  • M50 (K12) – 15,000 lbs truck at 50 mph
  • M40 (K8) – 15,000 lbs truck at 40 mph
  • M30 (K4) – 15,000 lbs truck at 30 mph
  • PU60 – 5,070 lbs truck at 60 mph
  • PU50 – 5,070 lbs truck at 50 mph

Click here to view the Stalwart crash-test video

Impasse II Maintenance Free Finnish

Ameristar's production facilities include a state-of-the-art polyester powder coating system providing all members of the Impasse family of fences with a finish that is far superior to other coatings in durability and scratch-resistance. The fence components can endure over 1,000 hours of salt spray testing; proving the claim of long-lasting durability.