Alarm system contains everything you need to secure your home. Base, Keypad, Panic Button, 8 Entry Sensors, 2 Motion Sensors, 2 Glassbreak Sensors, Keychain Panic button that arms and disarms alarm. The sensors are very easy to mount yourself with command strip tape or small screws (tape/screws not included) This is the 1st generation version. It works and is supported by SimpliSafe monitoring plans. See SimpliSafe for details on their plans. However if you want to add components to it (ie. Another entry sensor), you have to buy them from individual sellers here or on other sites. SimpliSafe doesn’t sell them anymore. Please see pictures.