O-rings are commonly used between two parts to create a seal, preventing gas or liquid from escaping. The O-ring is placed within a groove to keep it in place and then compressed by the parts on either side to ensure a flush seal. While there are many different sizes and diameters of O-ring available, there may be times when there is not a size available that is suitable or when standard sizes are either unavailable or too costly, and it is in these situations that an O-ring cord can be used. An O-ring cord is a rubber cord with a circular profile that can be cut to the required length to form the required seal. Types of O-Ring CordO-ring cords can be found in several different materials. Material selection for any application is based on chemical compatibility, application temperature, sealing pressure, lubrication requirements and durometer, with many options available in the following materials:Nitrile O-rings (NBR)Viton® O-rings (FKM)Silicone O-ringsNeoprene® O-ringsEPDM O-ringsWhere are O-ring cords used?O-ring cords are commonly used on non-moving machinery and static sealing applications to keep air, other gases and liquids from passing in or out of any given area. They are especially prevalent in pneumatic and hydraulic systems. O-ring cord has a clear advantage for fitting seals to special dimensions that ready-to-buy O-rings may not cater to.