Output amps are higher than manufacturer amps?
I have a HTC EVO V 4G phone and wish to buy a compatible car charger. The HTC charger provided with the phone for in-house use has an output of 5 v and 1 amp (HTC's on-line vehicle charger also has the 5v and 1 amp output). The output for the Rocketfish Moblile Vehicle Charger (model RF-DC1U2N) has a 5v and 2.1 output. Why does it have double the amps if it is suppose to be compatible? Is the double amp output safe for the phone / battery?