Metal Material- Our ssd mounting bracket is made of metal, which could strengthen the heat-sinking capability, so provides your hard drive a full protection.; 2.5" To 3.5" - 2.5" To 3.5" Mounting Adapter Bracket SSD Caddy, Support 2.5" hard drives (SSD and HDD) of laptop, compatible with SATA I, SATA II, SATA III.