O ring groove seal screws with sealing washers

O-ring (o-ring) is a kind of rubber seal ring with circular section. Because its section is o-type, it is called o-type rubber seal ring, also called o-ring.It first appeared in the mid-19th century, when it was used as a sealing element for steam engine cylinders.

The o-ring is the most common mechanical design for sealing because of its low price, simple manufacture, reliable function and simple installation requirements.