SPONGE, DRN AVANT 6PLY STR 4"X4" (25PK/BX 12BX/CS) 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 rayon/polyester sponge is highly absorbent, low-linting and fast wicking to wound beds