Avant Gauze Sterile Drain Sponge. 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. Each 6-ply sterile rayon/polyester sponge is highly absorbent, low-linting and fast wicking to wound beds. Drain not included.