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Square E400

Terra Firma E-Class E400 square access covers are the most advanced in-road lid on the market. Terra Firma Heavy Duty access covers offer strong, lightweight covers for in-road applications including high traffic freeway areas. They are suitable for in road applications and are independently tested to meet all standards of AS3996 D & E Class.

 Terra Firma E-Class square covers are made from advanced fibre glass composite material. Terra Firma access covers have been developed to give optimum performance and are significantly lighter than concrete and ductile options.

Terra Firma E400 composite range is robust and will not crack, warp, chip, swell, or expand. The stiff tensile structure resists all known forces under normal working conditions. Terra Firma E-Class are chemical, diesel, petrol, water and salt resistant.

Limited stock available, lead times apply.

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High structural performance

Structurally and fatigue tested. Meets AS3996 D & E-Class, AASHTO and European EN 124 D400 regulations.

Extended working life

Composite covers continue to perform well after 20 years in service. Will not break or spin out. The torsional resistant frames eliminate many of the usual causes of wear with traditional covers.

Permanent anti-slip

Exceeds 0.60 co-efficient of friction even when wet and will retain this anti-slip value throughout its working life unlike conventional metal covers.

Secure and lockable

Additional security may be included through a bolting system that automatically disengages when the cover is removed and reengages when replaced. High security key option is available. 

Injury free removal

Single person removal and replacement without the risk of back injury utilising Terra Firmas ergonomically designed lifting tool.

Reduced maintenance programmes

Longevity, ease of access and superior performance reduces maintenance programs. Fitting a Terra Firma cover is the best ‘whole life’ choice. 

No Residual value
Reduced risk of theft.


100% watertight/sand tight with a unique self-cleaning edge seal.


Covers can be vented which helps prevent the build up of gases.  Vents conform to ADA regulations.

 Transparent to radio waves

In pit radio transmitters are easily monitored through lids without the need to open pits.


Will not corrode when in contact with other materials. Unaffected by fuels, sand, salt and all chemicals met in road environments.

Electrically non-conductive

Will not conduct electricity, so stray voltage problems are negated.

Client design service

Terra Firma project managed bespoke design services will use our patented technology to design alternative size and colour solutions to meet customer requirements. Minimum order quantities and lead time applies.

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