Micro-USB chargers
It's good to see that the 351 (so presumably the others too) have a micro-USB charging socket. Maybe these devices are made by a Chinese company; the Chinese government mandated a single charging standard as way back as 2007.
I remember lots of the big players signing a Memorandum of Understanding to switch to micro-USB a few years ago but still some of them are still using propriety charging standards, it's about time they got their act together.