Synology Rail Kit RKS-02 Sliding rack rails for Synology rackmount servers. - Mount post width must be equal to or greater than 450 mm - Panel width must be equal to or greater than 480 mm - Rack mounting depth: 610 mm to 890 mm - Rack mounting hole support: square hole: at least 9.5 mm x 9.5 mm ; round hole: at least 7.1 mm