Note: These specs apply to each thingCHARGER. If you stack 2 or 3 together each will deliver as follows:

Specs You Care About:
Plug Type Twin Standard US 3-pin Plugs
(Called 'Type B' in international-speak)
Charger Output Voltage 5 Volts DC (The global USB standard)
Charger Output Amps 2.1 A (Enough for the hungriest tablets, or several smaller devices)
Charger Outlet Types Interchangable Charging Tips (Switch tips in seconds so anything can be charged)
2 x USB (on the underside)
Regular (Front) Outlets Standard US Twin Outlet (15 Amp max, voltage matches the input)
Input Voltage 108-252 Volts AC
(Just about every wall outlet on the planet)
Input Current 0.5 Amp Max (0.5 for device charging, more if the regular outlets on the front are used.)
Input Frequency 47 - 63 Hz
(Wow. If 47 Hertz, 63 must be agony!)
Weight 6.5 oz (185 grams)
Dimensions 3 x 0.8 x 4.8 inches (76 x 20 x 122 mm)
Specs You Probably Don't:
Input Voltage 108-252 VAC
Input Current 0.5 A RMS Max for charging + current used for items plugged into the front outlets
Input Frequency 47 - 63 Hz
Output Voltages 5 VDC for charging
108-252 VAC at the front outlets exactly matching input
Charging Output Current 2.1A Maximum Combined Current for Tip and both USB ports
Charging Output Power (Rated) 10.5w Maximum Combined Power for Tip and both USB ports
Output Ripple (Peak to Peak) 50 MV Measured at 20 Mhz Bandwidth with .1 Μf Ceramic Capacitor in Parallel with 10 Μf Electrolytic Capacitor Connected at the Output Connector at Nominal Line
Output Load Regulation + 5 % of Nominal Output Voltage, Measured at Output Connector at Nominal Line
Line Regulation + 2 % of Nominal Output Voltage, Measured at Output Connector
Turn On/ Turn off Overshoot ± 10% Max 500us Max Recovery Time for 0.1A to 2.1A Step Load
Turn-on Delay 1,000 ms Typical
Hold-up Time 8 Msec Min at Nominal Input and Full Load
Inrush Current 40 a Max at Cold Start 115 VAC
Switching Frequency 12khz - 40khz Depending on Output Load
Over-voltage Protection Protected, will autorecover on removal of fault
Over-current / Short Circuit Protected, will autorecover on removal of fault
Other Protection Input Line Fusing
Safety Approvals (Planned) Designed to Meet Ul1310
Dielectric Withstand Voltage 2,500 VDC Primary-secondary
Leakage Current 1MA Maximum at 132 VAC
EMI (Planned) Designed to Meet En55022 and FCC Part 15 Class B
CE Mark(Planned) Tested to comply with En61000-3-2, En61000-3-3, En60601-1-2 2001, Including En61000-4-2, En61000-4-3, En61000-4-4, En61000-4-5, En61000-4-6, En61000-4-8, En61000-4-11.
Mtbf 200,000 hours at 25°c ambient temperature
Operating Temperature 0°c to 40° C
Storage Temperature -10°c to 70° C
Humidity 10% to 90% Relative Humidity
Rohs Complies with EU 2002/95/EC and China SJ/T 11363-2006