Banggood

It's of good quality It has been successfully tested You can see the attached video for more details

Worked perfect with dual pack of CGR18650CG from my old battery laptop. I connected it to together and connect to old smartphone and after a while it start charging :)

Товар пришел, всё в порядке! Всё работает!) Теперь можно сделать поделки.)) The item came, all right! Everything works!) Now you can make crafts.))

Брал платку для маленькой солнечной панели. Со своей функцией справляется. Спасибо.

The circuit board is well processed, not all circuit boards from china are so well processed. (The fingerprints on the usb-port are my own fingerprints)

i ordered 2 boards and one had a cracked inductor. both tested with a 1.5v alkaline battery. 5.v on one board and 1.41v (same as input bat.) on board with cracked induct r. seems like a good product, just a shame one was broken

Fine for my needs. I got no more than 75-85% efficiency with a charged LiPo (4.18v) and various loads. Should get more efficiency with higher voltage but this is what I'm going to use it with. My photo shows it converting 3.65v from an old LiPo to 4.97v.

Very good module for DIY USB 5v Power Supply! An old plastic box, an old switch and a AA battery support. Is All!

Напряжение держит стабильно с током в 0,5 ампера справляется без перегрева

Step up converter as described.