The Astrolene yarn used in this dust mop is a blend of 4 synthetic fibres. Tightly twisted and heat-set, it resists fraying, does not produce lint, and stands up in the wash. This dust mop comes pre-treated with Velva Sheen dust control treatment; it can be re-treated after washing to maintain the dust-trapping properties of Velva Sheen. Slip-on style works with 5″ collapsible breakaway frames.