Powering an Arduino/stepper driver system with one DC input

http://www.ebay.com/itm/DC-to-DC-Converter-Step-Down-Module-7V-9V-12V-24V-to-5V-usb-output-power-adapter-/251278536206?pt=LH_DefaultDomain_0&hash=item3a815e2e0e

Feature:
Modules nature: non-isolated Buck
Rectification: Non-synchronous rectification
Input voltage: DC 7- 24V
Output voltage: DC 5V
Output current: 3A (max)
Conversion efficiency: 96% (MAX)
Switching frequency: 340KHz
Output ripple: 30mV (max)
Load regulation: ± 0.5%
Voltage regulation: ± 2.5%
Operating Temperature: -40 ° C to +85 ° C
With Overcurrent Protection

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