Differences between Power Supply models

I am very new to electronics, and I am just unsure of the differences between various Power Supply models.

In terms of using them in Arduino-related projects, what are the differences in these two 12V power supplies?

Power Supply 1

Power Supply 2

Why does one have a box attached in between the cords? Pros and cons of each when using in projects with Arduinos? Thanks!

The most important difference is that one can provide at most 2 Amperes of current, the other at most 5 Amperes.

Either will work with low current projects (no motors, a few LEDs). For a safety margin, if your project requires more than 1 Ampere but less than 5 Amperes, buy the second one.

One is a "wall wart" that plugs in directly to the house AC wall socket, the other has an extension AC cord.

jremington:
Either will work with low current projects (no motors, a few LEDs). For a safety margin, if your project requires more than 1 Ampere but less than 5 Amperes, buy the second one.

Thanks! For my project, it involves a 12V DC motor pump that draws around 0.2-0.3 Amperes. This will also be connected to an Arduino that utilizes 5V, powering a relay/12-5V Buck Converter, as well as a HC-SR04 sensor.
Would using the 5A power supply be better? Or would a 1-2 A wall unit also work?

The start/stall current of a DC motor as at least 5 times, and can be 10 times higher than the running current.

The 2A power supply may not be enough, so go with the 5A.

Do not connect 12V to the Vin of the Arduino. Instead power it using the 5V converter, connected to the 5V pin.

I agree. Go with the 5A rating one.