Hydrofera Blue CLASSIC PVA foam dressing uses two organic pigments gentian violet and methylene blue to deliver non cytotoxic antibacterial protection without releasing active substances into the Hydrofera Hydrofera Blue Classic Foam Dressings Hydrofera Blue Class Grayline Medical Hydrofera Blue READY Antibacterial Foam Dressing, 4 x 5 Inch Hydrofera Blue Classic Antibacterial Foam Mercari Hydrofera Blue Ready Antibacterial Foam Dressing 8" x 8" Medical Supply Surplus Hydrofera Blue Foam Dressing without Border 4 x 4 inch , 10 Count