The high-performance AGM battery in this model is specially formulated to jump-start vehicles The Sealey PBI4424GS is a DEKRA approved emergency jump starter, featuring a professional grade AGM battery that\'s specially formulated to jump-start vehicles. Unlike other booster packs, this unit can be left safely on charge continuously. It is fitted with a 12V accessory socket and a single 2.1A USB port ideal for charging mobile phones or tablets. Features: Professional grade, high-performance AGM battery, specially formulated to jump-start vehicles DEKRA approved emergency jump starter Includes an automatic maintenance charger with patented microprocessor controlled speed charging and thermal runaway protection Unlike other booster packs, this unit can be left safely on charge continuously Audible warning system (AWS) signals if the unit has been turned on for too long without being connected to a battery and reverse polarity Fitted with an isolating rotary on/off switch and features a digital display showing the internal battery level and the vehicle battery voltage Fitted with a 12V accessory socket and a single 2.1A USB port ideal for charging mobile phones or tablets A fusible link integrated into the output cable provides surge and spike protection, preventing damage to delicate and sophisticated vehicle electronics as well as the booster Specification:  Auxiliary Output: 1 x USB - 2.1A, 1 x 12V Cable & Clamp Length: 1.7m Nett Weight: 17.5kg Peak Amps: 4600A (12V)/2300A (24V) Starting Current: 1800/900A Voltage: 12/24V