We discovered, some poor extension uses cables to make inner connection with soldering.
Once a higher current passed through, each soldering connections will create electrical stress, the higher numbers of the soldering connection stress, the higher risk. Heat will be generated and may melt the inner soldered connection and may cause fire hazards.
A good quality extension socket should use solid brass strips for current carrying connection.
Since brass has a higher melting point than soldering connection and very good electrical conductivity, it will not melt when a higher current passing through. This makes it a good extension.
To find a good quality extension socket, please visit our website.