How do I make selection boxes being able to be seen through walls?

game.Players.PlayerAdded:Connect(function(p)
    wait(1)
    for i, v in pairs(p.Character:GetChildren()) do
        if v:IsA("BasePart") then
        local s = Instance.new("SelectionBox", v)
        s.Adornee = v
        end
    end
end)

I made this, but have no idea where to go from here. I have seen on certain games that you can see them through walls. Is it a property?