Avant Gauze Drain Sponges: 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. It'S A Simple Feature That Most Other Drain Sponges Do Not Offer. 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.  4" X 4", 6-Ply, Sterile 2'S.