" Standard Closures PP, Autoclavable Only for regenerated cellulose membranes. Lighter than water, normally used in combination with weighted closures. Choose a closure 4 to 10 mm larger than the flat width of the tubing. Weighted Closures PP with Fluorocarbon Coated Stainless Steel Bar Only for regenerated cellulose membranes. Used in combination with a standard closure for a vertical use of the dialysis tubing. Choose a closure 4 to 10 mm larger than the flat width of the tubing. Magnetic Weighted Closures PP with TeflonA Coated Magnetic Weight Only for regenerated cellulose membranes. Used in combination with a standard closure for a vertical use of the dialysis tubing and a magnetic stirrer for continuous stirring of the tubing. Choose a closure 4 to 10 mm larger than the flat width of the tubing."