Hollow pin chain is connected by hollow pins, and the hollow holes can be used to install various attachments for conveyor systems. This facilitates fixing attachments to outer links by bolting through the hollow pin and is suitable for use in all normal conditions. The attachments may be bolted up tight or held in the hollow bearing pin in a free manner. Bolted attachments should only span the outer link, as a bolted attachment spanning the inner link would impair the free articulation of the chain. In a hollow pin chain with single and double pitch, the hollow pins are the same as the bushings of the corresponding standard chain in diameter, and it can be said that a hollow pin chain is a bushing chain in which pins with the same diameter as that of the rollers of the corresponding standard chain are used as bushings.