Light weight.

All locking devices and hinges have undergone stringent fatigue test exceeding 250,000 cycles against sagging.

In locked position, the door leaf is secured by one strong lockset, 4 locking pins and 4 shear pins. All pins are made of grade 316 stainless steel with bronze bushes.

Door and ventilation sleeves are air tight and water proof.

Door leaf and frame are made of steel, and cathodic-electro-deposition painted to provide maximum protection against rusting.