How do i apply a color script from a value?

Sorry for the title, i can't really explain it from a title.

What i'm trying to say is that im trying to make:

mouse.KeyDown:connect(function(keys)
    if keys =="f" then
    if mouse.Target ~= nil then
        if mouse.Target.Material==Enum.Material.Pebble then
            local SelectBox = Instance.new("SelectionBox", mouse.Target)

            SelectBox.Adornee = mouse.Target    
            SelectBox.Color3 = Color3.fromRGB(script.Parent.Color.Value)
            print"done"


        end end
    end
end)

The Color Value is a color3 value, but when i use the script the selectionbox appears to be black?