Firstly, this is not an amplifier (as an amplifier is frequently defined). There are no batteries, amplification circuitry, or, (for that matter) speakers.
What this is, is a cleverly designed megaphone and iPhone stand. It takes the sound produced by your iPhone speakers and focuses is like a... megaphone. The result is decent quality, room filling sound.
The "device" is light and flexible, yet rigid enough to securely support my phone. I toss it in my suitcase without worrying about it being broken. There are no batteries or cables to worry about. And, for the price it can be replaced easily if I should misplace it.
This has become a staple in my carry-on (usually all I take when I travel) since it provides a lot of functionality with almost no additional bulk or bother.
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