Features: 1) Advanced internal structure design 2) Easy and fast to fix fiber cable 3) Easy to re-enter, it never requires re-entry kits 4) The closure is spacious enough for winding and storing fibers 5) Fiber optic splice tray (FOST) is designed in slide-in-lock and its opening angle is above 90 degrees 6) The curved diameter meets with international standard 7) Easy and fast to increase and reduce FOST 8) Innovative elastic integrated seal fitting makes it more easy and convenient for installation, maintenance and reuse 9) If required, the earthing deriving device can be installed on the housing of FOSC for deriving metallic parts of fiber cable for earthing connection 10) Pressure testing valve can be installed as well for pressure testing and sealing testing after injecting air