The cable factory locate in Guangdong China. I am not the manufacturer, I sell their product. The product standard is provided by the manufacturer. I cut one cable and test the ability of charging and data-transmission. The charging is fast, about 1% for 1 min, but it depend on what kind of phone, the battery, the voltage and the current. The data transmission is fast, can do copy and paste document fast. 
Attention:When opening a mobile phone folder on computer through the cable, if there is a lot of content in the folder, it maybe get stuck and become inoperable. It depend on the phone type and computer capability.

Standard
Length: 120cm
Minimum order is 2 cables, the order quantity increases by 1, which is the cable plus 2, like: order 2 quantity, get 4 cables.

The following are the factory tell me,I can't guarantee.
The maximum Current: 3A
Wire core material: Tinned Copper--from the cutting, can see the silver color,its the Tinned copper color.
Proctol: QC 3.0