RS PRO Elastomer O-Ring Cord, 2.4 mm Diameter, 8.5 m Length

As it's made from pliable elastomer rubber, the cord can be easily bent into most of the shapes you'll need. Its flexibility also means that it will spring back into its original shape when put under pressure, so you don't need to worry about it being permanently deformed. This material is chemical-resistant and won't be damaged by abrasive fluids. An elastomer cord like this one is suitable for pneumatic sealing applications where compressed air and gas are used. It contains only minimal levels of any harmful substances, so it complies with Restriction of Hazardous Substances (RoHS) standards.