It should be noted that the device was used under the following conditions: 1. Car: age - 2 years, 2.0 liters, 220 hp 2. Battery: 68 Ah, nominal voltage 12 V. 3. The car stood for 2 days at a temperature of -15, the voltage dropped to 9 V (that is, this is not a situation when the battery is discharged "to zero"). Perhaps suitable for starting small cars and medium-sized cars (with a not completely dead battery).