safely jump start a car

{"title":"Multi - Function Mini Car Jump Start Battery \/ 30000mAh 24v Battery Jump Starter","imgUrl":"https:\/\/img.silkroadsl.com\/nimg\/e7\/a9\/8e031551ec4f571de6893da9d78f-200x200-1.jpg","attrs":{"Price":"negotiable","Brand Name":"MAXKING","Model Number":"AL-JP27","Minimum Order Quantity":"1","Certification":"CE , ROHS , FCC","Place of Origin":"Guangzhou China","Payment Terms":"L\/C, T\/T, Western Union, D\/A, D\/P, MoneyGram","Packaging Details":"1*box","Type":"Jump Start","Start current":"400A","Peak current":"800A","Charging time":"7Hrs","Capacity":"30000mah(Built-in smart cable)","Input":"24V-30V\/2A","Output":"5V\/1A ; 5v\/2.1a","Operation temp":"-20\u2103\uff5e60\u2103; Lifetime: >1000 cycles","Size":"235*77*196mm"}}

{"title":"8000mAh Portable Jump Starters 600A 12V Emergency Car Charger Jump Starter","imgUrl":"https:\/\/img.silkroadsl.com\/nimg\/42\/71\/3a7e39736df9cb7c91d74cf852cc-200x200-1.jpg","attrs":{"Price":"To be negotiated","Brand Name":"XUWEN","Model Number":"12V 600A Portable Jump Starters","Minimum Order Quantity":"50PCS","Delivery Time":"To be negotiated","Certification":"CE ROHS,FCC,MSDS,UN38.3","Place of Origin":"China","Payment Terms":"T\/T, Western Union, MoneyGram","Supply Ability":"100000pcs\/month","Packaging Details":"International standard packaging","Product Name":"12V 600A Portable Jump Starters","Battery Capacity":"8000mAh","Battery Type":"Lithium ion Polymer (3.7V)","Input Voltage":"12V","Peak Current":"400A","Safety Protection":"Over-current, over-voltage, over-charge, short-circuit, over-discharge","Size":"140\u00d779\u00d714mm","Weight":"300g","Function":"jumpstart portable charger, portable auto jump starter","Vehicle Service Type":"Gas Engines up to 3.0L and Diesels up to 2.0L","Keywords":"portable battery jump starter, portable car battery charger jump starter","Color":"Blue, Yellow"}}

{"title":"45kg Portable Car Battery Charger 100 Amp Portable Charger Car Starter","imgUrl":"https:\/\/img.silkroadsl.com\/nimg\/a8\/21\/f56702cfb7927c760a08e93c11b9-200x200-1.jpg","attrs":{"Price":"$210.00 - $230.00\/Pieces","Brand Name":"OEM\/PONEY","Model Number":"CD-1000","Minimum Order Quantity":"50 Pieces","Place of Origin":"Zhejiang, China","Packaging Details":"STANDARD EXPORT CARTON","Supply Ability":"5000 Pallet\/Pallets per Month","Warranty":"1 Years","Color":"ANY","Output":"12V\/24V 100A","Input":"AC 230V","Weight(kg)":"45","Size(mm)":"290*320*630","Port":"NINGBO"}}