Biolite Charge 20 is a palm sized, reliable way to avoid the embarrassment / danger of running out of charge on your mobile phone or laptop.
Unlike dodgy but seemingly similar devices, the Biolite Charge 20 will charge an iPhone TWICE (and maybe half a laptop).
It’ll hold full charge for around a year.
Oh, and a silicone gasket makes this dunk-proof (just a tad shy of waterproof).
Specifications : Battery = 5200 mAh, 3.6 V lithium-ion ; Weight = 165 g, Materials = stainless steel, durable ABS plastic, silicone ; weather resistance = IPX6 (heavy splashes & rain). outputs (1) = USB @ 2.1 A , dimensions 21 x 38 x 98 mm