Used mainly in the automotive sector, SILS can expand to Sequenced In Line Supply, Supply In Line Sequence, and Synchronized in Line Supply, and is often used to mean the same as Just in Sequence (JIS) and In Line Vehicle Sequencing (ILVS). The SILS concept is that messages are generated as the vehicle moves along the production line. These messages trigger demand for the components which will be needed for the next several assembly steps. A successful SILS system will deliver the components just in time, presented to machines and operators in the order they will be used.