The Concertainer,^[1] known colloquially as the Hesco barrier^[2] or Hesco bastion,^[3] with HESCO being the brand name of the manufacturer, is a modern gabion primarily used for flood control and military fortifications.^[4] It is made of a collapsible wire mesh container and heavy-duty fabric liner and is used as a temporary to semi-permanent levee or blast wall against small-arms fire and/or explosives. It has been used during the war on terror in Iraq and Afghanistan.

It was originally designed for use on beaches and marshes for erosion and flood control.^[5] They were used in 2005 to reinforce levees around New Orleans in the weeks between Hurricane Katrina and Hurricane Rita.^[6] During the June 2008 Midwest floods, 8,200 metres (9,000 yd) of HESCO barrier wall were shipped to Iowa.^[7] In late March 2009, 10,700 m (11,700 yd) of HESCO barrier were delivered to Fargo, North Dakota, to protect against floods. In late September 2016, 16 km (10 mi) of HESCO barriers were used in Cedar Rapids, Iowa, for the fall flood of 2016.^[8]

The Concertainer was originally developed by Jimi Heselden, a British entrepreneur and ex-coal miner, who founded HESCO Bastion Ltd. in 1989 to manufacture his invention.^[9] Concertainer as the brand name for the barrier is a portmanteau of the words "concertina" and "container".^[1]

Assembling the HESCO unit entails unfolding it and filling it with sand, soil or gravel, usually using a front end loader. The placement of the barrier is generally very similar to the placement of a sandbag barrier or earth berm except that room must generally be allowed for the equipment used to fill the barrier.^[10]

The HESCO barriers are varied in sizes and models. Most of the barriers can also be stacked, and they are shipped collapsed in compact sets.

• 
  United States Navy Seabees assembling HESCO MIL units
• 
  Iraqi Army engineers fill a section of four-foot HESCO MIL with a wheel loader.

Since the original concertainer, HESCO has developed specialized variants:

• MIL is the basic earth-colored unit for military use. Example dimensions of typical configurations are 1.4 m × 1.1 m × 9.8 m (4.6 ft × 3.6 ft × 32.2 ft) to 2.1 m × 1.5 m × 30 m (6.9 ft × 4.9 ft × 98.4 ft).^[11] There is a "recoverable" variant with faster disassembly.^[12]
• FLOODLINE is a single-sized product for civilian flood control, colored green.^[13]
• RAID (Rapid in-theatre Deployment) is deployed from a container, which is dragged along the line of ground where the barrier is to be formed, unfolding up to several hundred metres of barrier ready for filling within minutes.^[14]
• HAB (Hesco Accommodation Bunker) combines a rectangular wall of MIL units with an aluminum roof and a pre-detonation screen.^[15]
• TERRABLOCK, a barrier combining concertainer ballast and metal mesh fencing. The largest "XV" form works as a M50P1 (ASTM F2656) vehicle barrier.^[16]
• LOPS (lightweight overhead protection system), a lightweight roof protecting against mortar fire.
• Sangar kits consisting of MIL walls, a protective roof, windows, and optional metal support.

• Bremer wall – steel-reinforced concrete blast walls

Wikimedia Commons has media related to HESCO bastions.

• HESCO Bastion Ltd—HESCO company site