A compact 40L universal underfloor water tank designed for campervans, motorhomes, caravans and other mobile applications. At only 16 cm high, its low-profile design makes it particularly useful where underfloor clearance is limited and interior storage space needs to be preserved.
 
Manufactured from durable, rotationally moulded MDPE, the tank is suitable for use as either a fresh water or wastewater tank.
 
Colour: Traffic Black (RAL 9017)
 
KEY FEATURES
Capacity: 40 litres
Dimensions: 75 × 37 × 16 cm (L × W × H)
Height: Only 16 cm
Weight: 4.5 kg
Material: MDPE
Wall thickness: Approx. 4–5 mm
Installation: Underfloor / horizontal
Lid: 12 cm flat inspection lid
Inspection opening: 10.6 cm
Connections: 1 × 1/2" BSP inlet + 3 × 3/4" BSP outlets
Vent points: 2 × vent connections
Temperature resistance: Up to +70°C
UV resistant: Yes
Baffles: No
Mounting kit: Not included
 
UNIVERSAL FITMENT
Rather than being designed around one specific chassis, the tank's simple 75 × 37 cm footprint makes it suitable for custom installation beneath a wide range of campervans, motorhomes, caravans and service vehicles.
 
The particularly useful feature is its 16 cm overall height, allowing water storage to be installed in relatively shallow underfloor spaces.
 
Always measure the available installation area and check surrounding components, suspension travel, exhaust clearance and ground clearance before ordering.
 
CONNECTIONS & VENTING
The tank incorporates:
1 × 1/2" BSP brass threaded inlet
3 × 3/4" BSP brass threaded outlets
2 × vent connection points
 
The threaded connections are supplied closed/undrilled, allowing the required connections to be opened during installation while unused ports remain sealed.
 
This gives the installer flexibility when configuring the tank for different water-system layouts.
 
FRESH OR WASTEWATER USE
The food-safe MDPE construction makes the tank suitable for fresh water storage, while its robust construction and multiple connection points also make it suitable for use as a grey/wastewater tank.
 
This makes it useful for anything from a compact fresh-water system to a dedicated underfloor grey-water installation.
 
MOUNTING
Mounting hardware is not included with this tank.
 
Installation must therefore be designed for the individual vehicle using suitable tank straps, stainless-steel brackets or a supporting frame.
 
A full 40L tank contains approximately 40 kg of water, so together with the tank itself the mounting system must safely support and restrain approximately 45 kg while the vehicle is moving.
 
IDEAL FOR
Campervan conversions
Motorhomes
Caravans and trailers
Fresh-water storage
Grey/wastewater storage
Service and commercial vehicles
Builds where low installation height is critical
 
WHY WE LIKE IT
At only 16 cm high, this tank provides a practical way to move up to 40 litres of water storage outside the living area without requiring a vehicle-specific tank.
 
Its universal dimensions, multiple connection points and fresh/wastewater compatibility make it a particularly flexible option for custom campervan builds.