Cable gland O-rings are used on the connection thread of a cable gland (a device used to secure the end of an electrical cable to electrical equipment) or similar part, to safely prevent oil, dust and water from getting inside the connection.
Cable gland O-rings are primarily used to prevent the loss of a fluid or gas. However, they can also be used as dust seals, drive belts or on rotating shafts.
O-rings are made from NBR (nitrile rubber) or thermoplastic. Both materials are resistant to oil, fuel and other chemicals, meaning O-rings are often used in the automotive industry to make fuel and oil handling hoses, seals and grommets.
Cable gland O-rings are simple to install. You simply guide the O-ring along the shaft of the cable gland until it snaps into place. If the ring is required to pass over threads, try to cover the threads as fully as possible, to avoid damaging the rubber. A light layer of lubrication can help.