The Caselabs Mercury S8 has a the XL-ATX form factor. XL-ATX is an unofficial larger version of the ATX standard which provides a larger alternative for even more space and ventilation. Using the XL-ATX standard, the case can house motherboards and power supplies with form factors ATX, E-ATX, Micro-ATX, XL-ATX and Mini-ITX. The dimensions of the case itself (LxWxH) are 369mm x 483mm x 476mm.

The Caselabs Mercury S8 has eight expansion slots, so there is plenty of room for extra components, which may be a deciding factor when planning on the longevity and build type of a PC system. The case has nine 5.25" drive bays, which is more than enough to house various drives, particularly optical drives. There are no 3.5" drive bays, though, so the large number of 5.25" drive bays is a necessity, particularly since there are also no 2.5" drive bays for an SSD or laptop-sized HDD.

Made primarily of Aluminium, the Caselabs Mercury S8 is built to be strong, lightweight, and well-ventilated. This often comes at a price premium, but some see the benefits to be completely worth it. Whatever your case's material, it is important to keep a consistent airflow so that heat doesn't build up inside. It is therefore advised that you make use of the available built-in case fans and fan installation sections.