PriorityStart! is an automatic computerized on/off switching system protecting battery voltage and starting power. If battery voltage drains below 11.7 volts when engine is off, it automatically DISCONNECTS the load. The battery voltage immediately recovers. To RECONNECT and START the vehicle: Just step on the brake pedal, activate the headlights, or use another accessory inside the vehicle, and starting power is automatically RECONNECTED! NO DEAD BATTERY! Designed to handle 1000 starting amps. PriorityStart! is not a battery charger or booster that is used after the battery has already been damaged. No waiting for emergency trucks, or calls for help. STAY SAFELY inside your vehicle. No lifting hood or attaching dangerous jumper cables. No buttons or switches to push. Pays for itself 1st time it saves you, ready to protect every time you need it. Using portable battery chargers/boosters, dangerous jumper cables, or calling a tow truck means you have already had a dead battery and done irreparable damage to your battery. (First time battery goes dead it loses 1/2 its service life). No hard wiring or modificatios. Transferable. Manufactured to ISO, USCG, and SAE standards. Maintenance free. Universal design on PriorityStart! works with 12-Volt top and side-post batteries. Same unit: Easily adaptable! No modifications are necessary. Pays for itself the first time you use it; ready to protect when you need it. Prevents lost wages and vehicle downtime. Saves cost of new battery. Protects expensive vehicle electrical parts. Protects from voltage spikes or surges.