Sponge Filter, Spare for SV-20 Wet & Dry Vacuum

On a wet and dry vacuum the foam filter is the one you fit before picking up water. It covers the motor intake and keeps the wet out of the windings, which is the whole reason the machine can do a job an ordinary vacuum cannot. Run it without the foam and the first bucket of water off a floor goes straight into the motor.

This is the spare for the SV-20, the 20 litre machine in the same range. Foam filters do not last indefinitely. They are washed after wet jobs, dried, and refitted, and each cycle takes a little out of them until the foam stiffens, tears at the edge that stretches over the cage, or splits along a fold. A torn foam filter still looks like a filter and passes dirty water through the middle of it. Because it needs to dry fully before it goes back on, a machine with only one foam filter is out of action for a day after every wet job, which is the practical reason to keep a second on the shelf in a workshop.