The batteries are an excellent product, the only issue I had was they did not fit the FeiyuTech G6 Gimbal as I originally bought them for as they are just a bit longer than the one supplied with this device (about 1.5 mm longer) I have however been able to use them else where successfully and they are working great. I believe that the Chinese manufacturers don't have quality control and their supplied batteries are not of a standard size and if it fails you cannot get a proper replacement not even from them?
About the product:
They charged up quickly considering the type of battery supplied most impressed with this, they also have a fairly long discharge rate as well exactly perfect for the use to which I have put them, thanks!!