Test of the Matek USB power monitor.

A quick test of my newly acquired USB power monitor. This unit is branded Matek and unlike most other USB power monitors that just show real-time voltage and current, this one can display A,V,W, mAh, duration and end of charge.
I got it from Banggood at:-
http://www.banggood.com/Matek-USB-LCD-Display-Voltmeter-Ampere-Meter-Power-Capacity-Tester-p-933952.html
One of the neatest things about this unit is that it detects end of charge of whatever you have connected by a settable current threshold (30mA default) and will actually turn the charge power off completely to your device and beep to let you know it's finished charging.
The fact it displays mAh (current over time) means that it will provide a modestly accurate indication of the capacity of the cells in a USB power bank if it is fully charged from being in it's low-charge cutoff state.
To restart the charging you can press the single button that is also used to cycle through various data. A blue LED in the unit indicates when output power is active. An LED in the display would have been nice.
First full charge-from-flat test I did was on the little pink USB power bank featured in another video. It showed a cell capacity of 1093mAh. Not quite the 2600mAh quoted on the packaging!