The GP Portable PowerBank 3C20A has a 20,000mAh lithium-ion battery that can recharge an Apple iPhone 6s Plus around seven times.
Available in black (version reviewed) or white, it has a power button and four-LED battery indicator in front. At its top are two USB output ports and a micro-USB charging port.
Measuring 20mm thick and weighing 356g, it is around the same size as my iPhone 6s Plus and feels like a hefty rectangular slab of plastic. But I was still able to grasp my phone with the 3C20A easily.
Its smooth surface means it can be a tad slippery, but it does not scratch my phone.
Using the 2.1A USB output port, the 3C20A clocked the fastest time in this round-up - 64min - to charge my iPhone 6s Plus, from 50 per cent battery level to full.
The biggest downer is its rather- hefty price tag, especially when the Xiaomi model with the same battery capacity costs only $39.99.
•Verdict: For those who do not mind its plain looks and price, the GP Portable PowerBank 3C20A will not let you down.
BATTERY CAPACITY: 20,000mAh
OUTPUT PORTS: 1 x 1.0A USB, 1 X 2.1A USB
VALUE FOR MONEY: 3/5