In that case the filter does not contain the key.

There has been some debate as to whether or not the filters for these masks contain asbestos.

Similarly, a filter on a set contains those subsets that are sufficiently large to contain something.

The problem: the filter contains about a quart of residual oil under pressure, which then overflows.

Intuitively, a filter on a poset contains those elements that are sufficiently high, according to some criteria.

This filter contains three sheets of different grade open-cell foam on the top, with Flocor filling the base.

A principal (or fixed, or trivial) ultrafilter is a filter containing a least element.

Felted filters contain randomly placed fibers supported by a woven backing material (scrim).

Maxwell took three identical pictures of a brightly coloured tartan ribbon, consecutively through three separate filters containing red, blue and green liquid.

Replies: Shaun, The simplest and probably the most economical approach to sulfur-fouled water is to pass the water through a filter containing activated carbon.