"Avant gauze drain sponge, 4"" x 4"", 6 ply, sterile 2's. This sponge features an extra fenestration which allows it to lay flat when wrapped around a drainage tube. Without it, the sponge will pucker, decreasing effectiveness by allowing fluids to pool around the drain tube. Includes all the benefits of non-woven Avant Gauze. Each 6-ply rayon/polyester sponge is highly absorbent, low-linting and fast wicking to wound beds. "