This International Standard specifies the requirements for a range of shackle type connector units for use with chain conveyors. Esch unit consists of the following components: a) shackle type connector; b) connector bolt; c) connector nut. This International Standard is not intended to indicate a complete design, but it gives sufficient detail to ensure dimensional compatibility with chains complying with ISO 610 and scraper bars complying with ISO 5612. The connector units specified are intended for use as part of 14, 18, 22, 24 and 26 mm diameter chain assemblies in which the connectors are fitted tightly on to scraper bars.