Hi, thank you for your product enquiry.
This British General Nexus Metal 2-Gang SP 13A Switched Socket + 4.2A 2-Outlet USB Charger Brushed Stainless Steel complies fully with the USB standard, which specifically limits the output voltage to 5V +/- 0.05.
If there are companies manufacturing `fast charge' sockets which output more voltage, or devices which demand more in order to charge faster, then these are not fully compliant with the USB standard.
Answered by: Nexus Technical Team
Date published: 2019-10-23