1. Detachable design, simple structure, practicability with low cost, easy to package, transport and assemble. 2. Able to add attachments which for optional (19 devices/cable manager/U type shelf/movable or fixed tray/etc.) 3. Meets the national standard 19, 1U=44.45mm as the distance of multiple to raise, 2 poles or 4 poles for standard. 4. Applying quality SPCC cold rolled steel sheet of 2.0 2.5mm, static loading capacity is up to 400KG. 5. Receive clients requirement or design drawing specializing.