Quantity   Component name
1 × Arduino Uno Any Arduino compatible with the relay and NFC sheilds will do.
1 × Maplin NFC Communication Sheild for Arduino Seeed and Adafruit NFC sheilds using the NXP PN532 are alternatives.
1 × Maplin Relay Shield for Arduino Any relay shield of your choice can be used.
1 × MULTICOMP G212 Enclosure An IP65 box so that the unit can be fixed outside if required. Alternative boxes need to be plastic!
1 × CML 190B1350 LED Panel Mount Indicator, Red An IP67 LED with integrated resistor for 24VDC operation
1 × CML 190A1351 LED Panel Mount Indicator, Green An IP67 LED with integrated resistor for 24VDC operation
1 × Velleman K1823 1A Power Supply Linear rectifier/regulator set to 9VDC output. A SMPS module would be better!