Quantity   Component name
1 × 220 Ohm resistor
1 × 1 female DC 2.1mm barrell jack
1 × 1 male DC 2.1mm barrell jack
1 × Adafruit PIR motion sensor https://www.adafruit.com/products/189
1 × 3xAAA Switchable Battery Pack
1 × Generic male header - 3 pins
1 × Generic male header - 2 pins
1 × Green (565nm) LED
1 × Cat Mate Pet Fountain http://www.pet-mate.com/uk/ShopOnline.aspx?Department_ID=1&Action=Home&category_id=289
1 × Golden GH-1C-6L AC relay
1 × BC548 NPN transistor