This article only applies to: Predator G3-571, G3-572, G3-573 and PH317 models.
Predator Helios 300 models have a storage bay to accomodate a 2.5" (9.5mm or 7mm) hard drive or solid state drive. You can use the to install a second drive. The drive configuration and storage specifications on these models are listed below.
Storage 1 = M.2 2280 for SSD (PCI/SATA)
Storage 2 = 9.5mm or 7mm HDD (2.5") available under HDD access panel.