Does 2.4 Amp car charger drains my iphone's 6s battery?

Hi everyone 🙂

I bought a 2.4 Amp Griffin car charger (12watt) .

They told me this charger gets 12v output and 5v inout .

I actually can't undrestand the difference between volt,amp and volt .

I just would like to know if this charger will drains my battery or it's not that bad ?!!

It's the overview of the charger if it helps ! ;

This low-profile charger works in the 12 volt accessory outlet in your car, and is optimized to deliver fast, safe charging levels for iPad, iPhone and iPod touch.

• Works in the 12 volt DC accessory outlet of your car's console or dash
• Includes detachable Lightning connector cable for charging and syncing
• Pull tab for easy removal
• Delivers 12 watts of charging power: 5 volts at 2.4 amps.

please help . Thanks