Some of the older ones come with a selection of interchangeable plugs that can be put onto the lead to fit any of the insanely wide variation of connectors that different phone handset makers used in the past.
I have a small solar one on the window ledge that has dug me out of a pit when the mains failed and my mobile battery was (of course) flat.
We have another compact more powerful one (~4Ah?) useful for extended playing with small gadgets on intercontinental flights.
I don't see the point in having anything more beefy since these days you can always recharge phones in the car or from any USB output. I just carry a 6" USB to uUSB lead.
Back when they were all on random connectors it made more sense.
Regards, Martin Brown