What I've never understood is, why?.... People that sell them say the flex in the plastic rod hurts acuracy... Umm... the work "guide" refers to guiding the spring... hte movement of the slide has nothing to do with the rod. It rides on the 4 rails. The only perpose of the rod is a smooth uniform compression of the spring during cycling. If the channel in the front of the frame was narrower and supported the spring better from all sides I bet you could shoot the gun without a rod at all. Ther is no load or force applied to the rod at all. It just keeps the spring form going "S" shaped in the frame channel. Plastic works fine for this.