Instruction:1. This power switch equipment is fit to all the kinds of mobile phone chargers， can’t be used for another purpose2. This product has the safeguard in currency， shortcircuit， over loading3. Plug this product into the cigarette socket4. Make sure the power indicator is bright5. Plug the mobile phone charger into this socket of this product6. This product is used for mobile phone， Personal Handy Phone System， travel charger. Can't be used to the ironheart for transformer.Caution:1. Some chargers with connector plugs reversely will not work， please counterchange the direction.2. This product is specially used for cathode grounded car， cant be used for anode grounded car.3. This product is specially fit to DC12V-24V car.