Dialysis tubing, visking. A transparent seamless viscose cellulose containing glycerine water and approximately 0.1% sulphur. Permeable to water and with an average pore radius of 24Å. Will permit diffusion of low molecular weight compounds in aqueous solution through the walls but retain high molecular weight compounds such as bacteria and proteins. Supplied as a flat roll in an airtight container. Dimensions given are inflated diameter x flat width and are approximate. Supplied in rolls of 30 metres.