Formerly called Elvstrom Bailers, these bailers use the boat's motion to create a Venturi effect which drains water through the bottom of the moving boat.
They are commonly mounted in dinghies and racing canoes.
Bailing capacity can be increased by mounting the bailers in pairs.

Automatic Bailers come in versions where the flange mounts on the inner surface of the hull, and versions where the flange mounts on the outside of the hull.
These are the inside mounting models.

Super Mini is smallest inside mounted bailer
The Super Mini Special is designed for racing dinghies where the bailer is operated from a hiking position, this bailer is mounted without spring lever
Super Max is designed for large hull thickness; large capacity makes it the perfect choice for high performance boats
Do not leave a dinghy equipped with an automatic bailer permanently in the water; a slow gasket leak could fill the boat
On outside mounted bailers, removing the spring lever while in the water could allow the bailer to fall out
Beware of open bailer edges when the dinghy is capsized
Made of stainless steel