It is used to measure the water permeability of plastic drainage board. The length of the sample is 330 mm and the thickness of the latex film is 0.3 mm. The pressure of 350 Kpa is added to the sample as required.

1. Sample Length: 440 mm

2. Head difference: 200 mm, hydraulic gradient 0.5

3. The effect and the stress above the specimen are: 0-500 kPa

4. The thickness of latex film is 0.3mm.

5. Shape size: 800 x 650 x 1920mm

6. Weight: 150 kg

The instrument consists of osmosis bin, water supply valve, upstream and downstream container, overflow pipe, rubber ring, latex film, pressure gauge, pressure reducing valve, regulating pipe, water level gauge and rigid cushion block.