It is a sturcture system for the ceiling. It is main include the following parts:

Main tee, Cross tee, Wall Angle; Hanger; Joiner;

As to the design, we can include seveal types: Common Tee Bar, Slotted T-bar, Wide or Narrow type T-bar and so on.

This is one kind of the suspending system for the ceiilng.
For the suspending system, our normal specification is:

Main tee: 32/38*24*3600
Cross tee: 27*24*1200
Cross tee: 27*24*600
Wall angle: 24*24*3000

Quantity reference: Main Tee 0.225 PCS/m2, Cross Tee (1.2 meter) 1.35 PCS/m2, Cross Tee (0.6 meter) 1.35 PCS/m2, Wall Angle 0.2 PCS/m2.