"xScale is not a valid member of UDim2"?

So I'm trying to move a GUI using tweening, and I've got most of it together, but for some reason, I keep getting this error "xScale is not a valid member of UDim2." This is the exact code I'm using

local FuelLeftProperties = {

		size = UDim2.new(CurrentFuelGUI.Size.xScale,CurrentFuelGUI.Size.xOffset - FuelDecreaseNum, CurrentFuel.Size.yScale,CurrentFuel.Size.yOffset)

	}

I can't figure it out, then again I have not done much work with UDim2 values so maybe im doing something really stupid.

the property is Size.X, i dont think it is Size.xScale