When modding Fallout New Vegas, you will come across mods that add new features like weapon inspects and ammo checks.
To use the features you will need to press a button.
In most cases if you want to change/customize what button you want to use, you can pause the game and go into the MCM (mod configuration menu) find the mod and change the buttons.
But this is not always the case.
The mod maker needs to make this a feature and they don't always do it.
In most cases however, they do add an ini. file that allows the user to customize settings on their own.
But of-course it's not as easy as just saying ''use key X to activate the mod feature''.
No, Fallout New Vegas uses DirectX to represent keyboard keys.
And you will need to change these numbers to your desired key.

In the next section I will list all the codes you use and their corresponding keyboard key.
The important parts to look at are:
Dec - for the number
Button - for the button you want it to become

But for now I will first show you an example of how to use these codes and change a mod key use.
For an example we are gonna use ''Tactical Freelook - ESPless''
https://www.nexusmods.com/newvegas/mods/93490

First make sure the mods works that you are gonna use, make sure all the requirements are met and that you can use the mod in game.
Now outside of the game we need to find where the mod is installed and find the customization ini. file.
To find it in your game files, I recommend:
Right click on the game in your Steam library.
Browse local files.
Then go into the Data folder.

Now to make it easier on you, go to the download link of your mod, click on files and click ''Preview file contents''.
This will show you the file structure and what path you will need to take to get to the ini. file.
Just follow the folders till you find the ini. file and open it, if it ask with what program use notepad.

In this case we need to go to:
📁 Config > 📁 Stentorious > 📄 Freelook.ini (1.3 kB)

Now we need to find where it uses the code for the key.
Here it's iKeyBind = 56.
Change the 56 to the number/letter you want (See below section).

Make sure to save and now you can head back in game to test out if it worked.

Hex

Dec

Button

0x01

1

Escape

0x02

2

1

0x03

3

2

0x04

4

3

0x05

5

4

0x06

6

5

0x07

7

6

0x08

8

7

0x09

9

8

0x0A

10

9

0x0B

11

0

0x0C

12

Minus

0x0D

13

Equals

0x0E

14

Backspace

0x0F

15

Tab

0x10

16

Q

0x11

17

W

0x12

18

E

0x13

19

R

0x14

20

T

0x15

21

Y

0x16

22

U

0x17

23

I

0x18

24

O

0x19

25

P

0x1A

26

Left Bracket

0x1B

27

Right Bracket

0x1C

28

Enter

0x1D

29

Left Control

0x1E

30

A

0x1F

31

S

0x20

32

D

0x21

33

F

0x22

34

G

0x23

35

H

0x24

36

J

0x25

37

K

0x26

38

L

0x27

39

Semicolon

0x28

40

Apostrophe

0x29

41

~ (Console)

0x2A

42

Left Shift

0x2B

43

Back Slash

0x2C

44

Z

0x2D

45

X

0x2E

46

C

0x2F

47

V

0x30

48

B

0x31

49

N

0x32

50

M

0x33

51

Comma

0x34

52

Period

0x35

53

Forward Slash

0x36

54

Right Shift

0x37

55

NUM*

0x38

56

Left Alt

0x39

57

Spacebar

0x3A

58

Caps Lock

0x3B

59

F1

0x3C

60

F2

0x3D

61

F3

0x3E

62

F4

0x3F

63

F5

0x40

64

F6

0x41

65

F7

0x42

66

F8

0x43

67

F9

0x44

68

F10

0x45

69

Num Lock

0x46

70

Scroll Lock

0x47

71

NUM7

0x48

72

NUM8

0x49

73

NUM9

0x4A

74

NUM-

0x4B

75

NUM4

0x4C

76

NUM5

0x4D

77

NUM6

0x4E

78

NUM+

0x4F

79

NUM1

0x50

80

NUM2

0x51

81

NUM3

0x52

82

NUM0

0x53

83

NUM.

0x57

87

F11

0x58

88

F12

0x9C

156

NUM Enter

0x9D

157

Right Control

0xB5

181

NUM/

0xB8

184

Right Alt

0xC7

199

Home

0xC8

200

Up Arrow

0xC9

201

PgUp

0xCB

203

Left Arrow

0xCD

205

Right Arrow

0xCF

207

End

0xD0

208

Down Arrow

0xD1

209

PgDown

0xD2

210

Insert

0xD3

211

Delete

0x100

256

Left Mouse Button

0x101

257

Right Mouse Button

0x102

258

Middle/Wheel Mouse Button

0x103

259

Mouse Button 3

0x104

260

Mouse Button 4

0x105

261

Mouse Button 5

0x106

262

Mouse Button 6

0x107

263

Mouse Button 7

0x108

264

Mouse Wheel Up

0x109

265

Mouse Wheel Down

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