But she had time to think about it now, only to see that her eyes were already at the level of the vent, and her other hand quickly grabbed the wall on the vent, and stuffed the black trench coat in her hand out of the vent.

Looking at the night sky full of stars outside the vent, Fang Yanan seemed to see the hope of life again.

At this moment, an incredible thought suddenly flashed through her mind, the man she was stepping on was the messenger sent by heaven to protect her, and once again pulled her back from the brink of death.

Everything is going according to plan, thanks to Fang Yanan's solid dancing skills, otherwise she might not be able to climb out unharmed.

Although it took a lot of effort for her to get off the rope, she still landed safely after all. Except for some dirt on the body, there were some scratches on the arms and insteps, and the rest were basically unharmed.

Outside the vents was an open, grassy wasteland. With the help of the hazy moonlight, at a glance, there was a large black and oppressive field of wild grass that was more than a person tall. A gust of autumn wind swept by, swaying back and forth, as if countless figures were dancing in the eerie night, giving people a chilling and eerie feeling.

Fang Yanan couldn't help but shudder and gasped.

But at this point, there's nothing to be afraid of.

Fang Yanan, who stared at the surrounding situation with wide eyes and alertness, tried his best to calm down his frightened emotions.

I saw that after she took a deep breath, she quickly found her black high heels and the black windbreaker that Ye Sanping gave her.

Then he lifted a high heel and knocked the stiletto heel as thick as a little finger against the wall three times.

This is what she agreed with Ye Sanping in advance, as long as she lands safely, she knocks on the wall three times, which means that she is already safe.

After putting on the high heels and the trench coat, it had been five or six minutes since she landed, and fortunately she was still standing on the ground alive, which also proved that the killer had not found her, otherwise, before she landed, I am afraid that she would have died in the west.

Fang Yanan knew in her heart that she had finally escaped this catastrophe safely. Despite this, her face still did not show the slightest joy of the aftermath of the catastrophe, but became more and more sad.

Ye Sanping, who had safely escaped Fang Yanan out of the vent, heard three taps on the wall not long after. Seeing that Fang Yanan was temporarily safe, he could be regarded as relieved.

After taking care of Fang Yanan's affairs, Ye Sanping basically didn't have any worries anymore.

For top-notch night vision equipment such as infrared sights, Ye Sanping is very familiar.

In fact, the so-called infrared sight is one of the night vision devices (DNV), the earliest night vision systems developed by the United States, they were used in the battlefields of World War II and the Korean War, these NVD systems use active infrared technology.

Such beams cannot be seen by the naked eye, they are reflected off the object and then returned to the lens of the NVD.

At present, the US military uses third-generation technology. Although the principle is not fundamentally different from that of the second generation, the resolution and sensitivity of this generation of NVDs are better. This is because its photocathode is made of gallium arsenide, a substance that helps increase the efficiency with which photons are converted into electrons. In addition, the MCP is coated with an ion barrier layer, which can effectively increase the life of the pipe.

These infrared sights, also known as sightscopes, are usually hand-held and can also be mounted on weapons, and they use a monocular (one eye) body. Since the scope is a handheld device and is not worn on the body like an eyepiece, it is suitable when you want to make a more detailed observation of a specific object and then return to normal observation conditions.

It works by using a special lens that concentrates the infrared rays emitted by objects in the field of view. This is also known as thermal imaging.

There are generally two main categories of thermal imaging equipment:

Uncooled - This type of thermal imaging device is the most common. Its infrared detector element is encapsulated in a single unit and can operate at room temperature. Such a system activates quickly, works completely silently, and has a built-in battery.

Cryogenic cooling - This system is more expensive and can be easily damaged if not operated properly. This thermal imaging device encapsulates the detector element in an outer package and cools it to below 0°C. Due to the cooling of the detector element, such a system has extremely high resolution and sensitivity. The cryogenic cooling system can "see" a temperature difference of 0.1°C from a distance of 300 meters, so that the system is enough to tell if a person is holding a gun in his hand!

Although Ye Sanping had used these two thermal imaging devices in the past, he was not sure whether the other party was using the non-cooled type or the low-temperature cooled type.

However, one thing is certain, judging by the domestic market situation, the high-end technical products of the cryogenic cooling type are not only very expensive, but also belong to the military's control equipment, which is definitely not so easy to obtain.

If it's abroad, that's a different story.

Therefore, Ye Sanping estimated that the sight used in the killer's hand should be equipped with thermal imaging equipment, and it should be non-cooled.

But this is just his speculation for a while, and he is not completely sure that the other party is using a non-cooling type, and it is possible that this top assassination master has come across the ocean!

It should be certain that the killer is using a sniper rifle equipped with a thermal imaging sight. As long as it was night, anyone appeared in that open-air courtyard, and it was absolutely impossible to escape his bullets.

Because the human body is emitting heat energy to the outside world all the time, as long as it appears in his sight, it is impossible to escape, unless the surface of the human body is wrapped in a substance that can quickly lower the temperature of the body surface, such as the mud of ice water.

The only thing that can be determined at the moment is the direction where the killer is hiding, and maybe you can start from this aspect and think of a good way to escape!

This book was first published from 17k, the first time to see the genuine content!