Features:
Can use the computer USB port 5V power supply
or using a mobile phone charger USB port 5V power supply
battery power can also be used
high efficiency:90%
can provide 3W (left channel) +3 W (right channel) output power in the 4Ω load and 5V power supply conditions
A class, B class amplifier such efficiency is only about 30%
D class amplifier is highly respected today 
D class amplifier efficiency is extremely high, not because of temperature affect the sound quality
but do not add heat sink and take less space
noise canceling circuit was built in the amplifier board
power on / off without pop noise
module has a short-circuit current protection and over-temperature protection
Application:
LCD TVs, monitors,
Laptop
Portable Speakers
Portable DVD players, game consoles
Phone / speakerphone

Specifications:
Operating voltage: 2.5V-5.5V
Speaker With:4-8ohms  recommended:4 ohms
Speaker Power :2-8W

Size:21 x 18 x 3.4mm(L x W x H)
Color:As the pics show
Net weight:1g
Package weight:11g

Package include:
1 x amplifier board

PROMISE : 
We offer 100% Customer Satisfaction , if you have any questions , please let us know and we will do our best to rectify the situation . We fully stand behind with all the items that we are selling ! When you receive your item , please leave positive feedback , we rely on you for our good name !