How long does the 3000mAh battery last?

The listing gives no runtime figure. A 3000mAh cell is roughly double a typical small clip fan's battery, so expect longer runs than budget clip fans, but actual hours depend on the speed you use.

Does the LED display show battery percentage?

Yes. The built-in screen shows the exact battery percentage, so you can see how much charge is left instead of guessing from a single indicator light.

What can it clip onto?

The clip is designed for backpack straps, sun umbrellas and car seatbelts. Thick or rounded surfaces may not grip as securely as a flat strap.

How do you charge it?

It charges over USB. The listing does not state the connector type or charging time, so check the port on the unit before you buy a cable.

Does it have speed settings?

The listing describes a high-velocity cooling system but does not list the number of speed settings. Confirm the controls before buying if you need adjustable speeds.