The invention relates to a roller, wherein the roller is designed as a roller unit (L), comprising at least one attachment socket (3), a bearing (2) and a roller (1). The invention also relates to a roller device, comprising an attachment bolt (4) and a roller arranged on the attachment bolt, wherein said roller is a roller according to at least one of claims 1 to 7. The invention further relates to a link chain, wherein the link chain is provided with a roller according to at least one of claims 1 to 7 or with a roller device according to at least one of claims 8 to 15. Moreover, the invention relates to the use of a link chain according to at least one of the preceding claims as a conveying chain.
