Keypad Tool with Wire Support by Willox

This download looks like an addon. You need to extract the downloaded zip and put the addon folder in your Garry's Mod addons folder. You should end up with a directory structure similar to below:

• steamapps
  • common
    • garrysmod
      • garrysmod
        • addons
          • gmod-keypad-master <-- Addon folder!
            • e.g.
            • lua
            • maps
            • materials
            • models
            • etc

• gmod-keypad-master/
  • LICENSE
  • README.md
  • addon.json
  • lua/
    • autorun/
      • client/
        • keypad.lua
    • entities/
      • keypad/
        • cl_init.lua
        • cl_maths.lua
        • cl_panel.lua
        • init.lua
        • sh_init.lua
      • keypad_wire/
        • cl_init.lua
        • cl_maths.lua
        • cl_panel.lua
        • init.lua
        • sh_init.lua
    • weapons/
      • gmod_tool/
        • stools/
          • keypad_willox.lua
          • keypad_willox_wire.lua
      • keypad_cracker.lua

Lunar CaT, lorenzo, traiteurducarne59440, oops_wine, Skysnow, Egemen, hodos.t, Tremb.Tyler, ~r~ [SEAL] ~b~ E-3 (SN) Jac M, Chris Lacaille, Ant, nut0990935992, Nightwolf521223 pvpro.com, phoenix, uyuyu, m1xaxxpro, csgocases.com s͏u͏p͏r͏e͏me, LittleCarbon, Mrdanilka22, shaziazafar787, Meinl Man, lexa.sibaev, danjchapman, Dwiazz, espadocarreira, cat.obormotiki, DeJV, NozaxzYoutube_, Traavviisss, carlosdavidnunez, МЯУ МЯУ МЯУ МЯУ✅, -hokage, angetalleux2009, Aeugh644, BlockMan, prototypegamer360, brayanmanzailapro, Matt:), TheZombieMan, igrushki888731, igrushki888731, VanessaMXS, MR POOPER, SCP- combine HACKER, Dono0530, lapuskinnikita0, hofmaster, feptik, FlaTyBoom, carmelomale666 +3267 others