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STAKKAbox™ Fortress is a range of modular and structural preformed access pits, suitable for use across all major industry sector projects.

The Fortress system is moulded in HDPE and possesses excellent strength to weight properties.

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Features & Benefits

Fast and Easy to Install

STAKKAbox™ pits are significantly faster to install than conventional alternatives, with complete installations typically taking up to one hour. This results in reduced costs for the installer. No specialist equipment or plant is required in order to install the pit and there is no need for specialist box builders.

Sectional & Twin Wall Design

Pits are built to required depth by adding 150mm sections. Due to the twinwall design, individual sections are lightweight, making them suitable for manual lifting. Each access pit possesses vertical and horizontal ribs, resulting in a product that is strong both vertically and on the sidewall. Most installations do not require specialist backfills, reducing installation costs.

Flexible During Installation

Pits can be adapted to suit on site conditions with standard tools to overbuild over existing networks, Introduce duct entries for cable entry and for top-section fine adjustment.

Smooth Outer Walls with Lip to ‘Key In’

Gaps in the outer wall will negatively impact the effectiveness of compaction around the pit. STAKKAbox™ pits have smooth outer walls and an outer lip which keys into the backfill.

Flat Pack Option

Fortress can be supplied in 'flat pack' format to make shipping more efficient, as well as allowing flexibility in delivery and installation.



STAKKAbox™ Fortress is manufactured in nitrogen-foamed High Density Polyethylene (HDPE), of which up to 70% is recycled material.

HDPE possesses excellent strength to weight properties.


Available Sizes

Sizing Information

STAKKAbox™ Fortress pits are formed by combining four interconnecting component parts to form each ring section. These sections are locked and secured using supplied screws. Using standard component parts allows for greater flexibility in pit size and clear opening.

For further sizing information contact the Cubis Specialist Team on 1800 065 356.


Load Rating

STAKKAbox™ Fortress is suitable for installation in environments rated up to Class C load rating (ultimate limit state design of 150kN) under the Australian Standard AS/NZ 3996.

This makes the STAKKAbox™ Fortress system suitable for residential roads and car parks trafficable to vehicles.


Options & Accessories

STAKKAbox™ Fortress can be supplied with the following accessories