An expandable slot refers to a space in a device where you can attach additional components, such as memory cards or expansion cards, to increase its functionality or capabilities. Full definition
Some details, the Huawei Mate 9 is a high - end smartphone powered by Kirin 960 chipset, paired with 4 GB RAM and 64 GB storage with expandable slot. (pokde.net)
It has hybrid slot which can act as dual sim slot or expandable slot. (maktechblog.com)
It has hybrid slot, which means it can be either used as a dual sim slot or expandable slot. (maktechblog.com)