How do I make every hat in a player transparent?

See, the issue with changing transparency this way is that you don't know the hat's name. That means you'd have to loop through items to see if they're a hat. But then you could just include the parts in the loop. Here's how I'd do it:

--This will not work for FE games, or would only show him his own body as transparent
local plr = game.Players.LocalPlayer
local debounce = true
function onKeyPress(inputObject, gameProcessedEvent)
    if inputObject.KeyCode == Enum.KeyCode.Z and debounce then
			debounce = false
			for a,part in pairs (plr.Character:GetChildren()) do
				if part.ClassName == "Part" then -- their torso,head,legs and arms
					part.Transparency = 1
				elseif part.ClassName == "Accessory" then
					part.Handle.Transparency = 1-- this should make all hats transparent now
				end
			end
			wait(1)
			debounce = true


    end
end

game:GetService("UserInputService").InputBegan:connect(onKeyPress)