Why is My SelectionBox script Not working Correctly?

Im wanting the color of The SelectionBox to be Really black, But Instead it Goes to its default color, Any reason why???

while wait() do
 for _,v in pairs(game.Players:GetChildren()) do
	local torso = v.Character:findFirstChild("HumanoidRootPart")
	if torso:IsA("Part") then
		x = Instance.new("SelectionBox")
		x.Parent = torso
		x.Adornee = torso
	end
	local find = v.Character.HumanoidRootPart:findFirstChild("SelectionBox")
	if find then
		find.Color = "Really black"
	end
end
end

while wait() do
 for _,v in pairs(game.Players:GetChildren()) do
    local torso = v.Character:findFirstChild("HumanoidRootPart")
    if torso:IsA("Part") then
        x = Instance.new("SelectionBox")
        x.Parent = torso
        x.Adornee = torso
    end
    local find = v.Character.HumanoidRootPart:findFirstChild("SelectionBox")
    if find then
        find.Color = BrickColor.new("Really black") --It's a brick color. Therefore, you need BrickColor.new.
    end
end
end