ISO 3166-2 geocode for Argentina. This is used as an international standard for shipping to Argentina. Each Argentinian province has its own code with the prefix AR.. For example, the code for the Province of Buenos Aires is ISO 3166-2:AR-B.
The USB 2.0 interface can be a limit due to signalling and command overhead as well as spacing between packets. I have a fast SSD connected by USB 2.0. The drive is much faster than the interface (by more a factor of 10). Read Speed maxes out around 33 MB/s and Write Speed at 17.5 MB/s. Write Speeds are almost 50% slower due to a verify-read after the write and the fact that the USB signal is half-duplex as another answer mentions.
USB 1.1 could transfer data at 12 Mbit/s. That is 1.4 Megabytes per second. Back in the day when a floppy disk could hold 1.4 Megabytes, that was fast. USB 2.0 was released in 2000, sporting a theoretical throughput of 480 Mbit/s. However, practically it works at 280 Mbit/s, which is around 35 Megabytes per second.