What does the security door D mean, when buying an security door, look at the sample, thick and heav

The anti-theft door is divided into grades, the thickness of the Grade A security door is about 2 mm, the security door is used in fire and sound insulation, heat insulation and thermal insulation performance of aviation honeycomb aluminum or aluminum silicate rock wool, etc., like the anti-theft performance of the lock of the Grade A security door is B-level, which is what we call the advanced protection level, the Grade A anti-theft door will be more durable.

Gives you all the standard standards for a Class D security door, including the locking point. >>>More

The anti-theft door is divided into grades, the thickness of the Grade A security door is about 2 mm, the security door is used in fire and sound insulation, heat insulation and thermal insulation performance of aviation honeycomb aluminum or aluminum silicate rock wool, etc., like the anti-theft performance of the lock of the Grade A security door is B-level, which is what we call the advanced protection level, the Grade A anti-theft door will be more durable.

Boundless means that the security door does not have edging. Hemming is to play an anti-theft role, there are single or yard slag edging, there are also double edging. Is there an inner edging or an outer edging. >>>More

A, B, C key lock, it has A, B, C three keys. The function of the A, B, and C keys is that when people install the lock, the owner can hand over the A key to the house decoration personnel for them to unlock the door in and out of the house, so the A key is also called the "decoration key"; The C key can also be used normally. When the decoration is completed, the owner does not need the decoration personnel to enter the room, the owner inserts the B key into the lock hole and turns the lock cylinder (circle), the A key loses the function of unlocking, and the key can be used normally in the future. >>>More