system is made in the method that perforated and non-perforated
panels of the leveled rectangular shapes using aluminum
or steel are installed lengthwise and crosswise. According
to this system's uses, equipments for lighting, air-conditioning,
communication and fire extinguishing, etc. can be designed
in accordance with ceiling in various ways. Specially,
if perforated panels are used, the sound absorbing effect
is the largest.