How would you go selecting certain parts of a model in a script ?

I was creating a tool, and i wanted to select certain parts of a model to make that, when i unequip it will wield onto your waist. Problem is that it turns the transparency of **EVERY part, i only want 2 parts to be opaque (A Union and a part) And not to show the grip (Handle). Any help would be really greatful ! :)

PS : You don't have to worry about the other stuff, since it works just fine. This is a server script and is located in the ServerScriptService, ask me if you don't understand.

local radio = game.ServerStorage.Radio ---- Variables 
local radio_c = radio:Clone() 
local c_kids = radio_c:GetChildren

game.Players.PlayerAdded:Connect(function(plr)          
	plr.CharacterAdded:Connect(function(char)
		local RightWaistAttachment = Instance.new("Attachment")
		RightWaistAttachment.Name = "RightWaistAttachment"
		RightWaistAttachment.Position = Vector3.new(0.8,-0.6,-0.5)
		RightWaistAttachment.Parent = char.Torso 
		local M6D = Instance.new("Motor6D")
		M6D.Name = "ToolGrip"
		M6D.Parent = char.Torso
		local Weld = Instance.new("Weld")
		Weld.Name = "Radio_Wield"
		Weld.Part0 = radio_c.PrimaryPart
		Weld.Part1 = char.Torso
		Weld.C0 = Weld.Part0.RightWaistAttachment.CFrame
		Weld.C1 = Weld.Part1.RightWaistAttachment.CFrame 
		Weld.Parent = Weld.Part0
		radio_c.Parent = workspace
		for k,Part in pairs(c_kids) do
			Part.Transparency = 1 
		end
	end)
end)

game.ReplicatedStorage.ConnectM6D.OnServerEvent:Connect(function(plr, location)

	local char = plr.Character
	char.Torso.ToolGrip.Part0 = char.Torso
	char.Torso.ToolGrip.Part1 = location
	for k,Part in pairs(c_kids) do ---This
		Part.Transparency = 1
		end  
end)

game.ReplicatedStorage.DisconnectM6D.OnServerEvent:Connect(function(plr)
	plr.Character.Torso.ToolGrip.Part1 = nil
	for k,Part in pairs(c_kids) do --- And this 
				Part.Transparency = 0 
	end 
end)