Chain

The present invention provides a chain. The chain which comprises a pair of inner link plates which have opposite configurations; a bushing inserted into a first through hole of each of the inner link plates and having two terminals protruding out of the inner link plates; a pin which is inserted into the bushing; a pair of outer link plates arranged in a manner of clamping the outside of the pair of inner linking plates and having two terminals inserted though a second through hole of the outer linking plates; and ring shaped sealing components which are respectively engaged with the two terminals of the bushing and arranged between an outer side surface of each inner link plate and an inner side surface of each outer link plate. An inner-peripheral side sealing ring is slidably connected to the outer link plate under the condition that a compressed first elastic ring is clamped between the inner-peripheral side sealing ring and the inner link plate. An outer-peripheral side sealing ring is slidably connecte