Apollo Intelligent Twin Input/Output Unit provides the function of two Input/Output units within one enclosure. The two units are electrically independent of each other. There is a DIL switch on each unit to set the address. Both Input/Output units in the enclosure provide supervision of one or more normally open volt free contacts connected to a single pair of cables and a set of changeover relay output contacts. This unit is available in the new faceplate style enclosure. This can be mounted with the supplied backbox for surface mounting or flush mounted using a UK double gang, flush mounting back-box of minimum depth 30mm. The Intelligent Twin Input/Output unit complies with the essential requirements of the EMC Directive 2014/30/EU, provided that it is used as described.