45 lb.Uniform-Density Foam, Resists Chemicals, For Labware Type Vials, Liner Material Plastic, Package Quantity 80 Stopper, Stopper Size 46-50 mm, Neck Size 46-50mm, Screw Closure Size 46 to 50 mm, Material Foam, Product Type Foam Plug, Color White, Autoclavable Yes, Special Features Breathable and Non-Absorbent, Open-Cell, 1..