These tubes are small sized (about 16 mm) thin walled porous flexible hoses made from polyethylene (PE) fibres, PVC or rubber. They permit water and nutrients under low pressure to pass from inside the tube by transpiration and irrigate the crops.

The porous pipeline discharge is not accurate, because the size of the pores varies and is not stable.

It is more common and mostly used in the landscaping irrigation than in the agricultural irrigation.