AEDs or automated external defibrillators are portable electronic devices used in cases of life threatening cardiac arrhythmias which lead to cardiac arrest. AEDs are designed to be simple to use and the use of them can typically be learned in many first aid, first responder and CPR classes. AED machines can be found in emergency vehicles as well as areas where large groups of people gather. AED machines are usually made to be highly visible and colorful. AED machines typically include a face shield for providing a barrier between patient and first responder during rescue breathing, a pair of rubber gloves, a pair of trauma shears for cutting through a patient\'s clothing to expose the chest, a small towel for wiping away any moisture on the chest and a razor. AED sales are aimed towards public and professional use.