Modular design, easily assemble and disassemble for delivery, low-cost. Various optional accessories , 19"frame ... 1) Comply with ANSI/EIA , RS-310-D ,IEC297-2 , DIN41491, PART1, DIN41494, PART7, GB/T3047.2-92 standard .2) Modular design, easily assemble and disassemble for delivery, low-cost. 3) Various optional accessories according to requirements ( cable management slot, cable management, ...