Expander module with 8 inputs expandable to 16 and 8 OC outputs with connectors for ATS1810, ATS1811 o ATS182 boards in a plastic box ATS1647 (included) with tamper. Up to 16 relay outputs by outputs boards. Power sourced by the same bus. Dimensions: 120 X 240 X 40 mm. Security grade 3 certified.