There are distinguishable differences between the EMD models and the Canadian GMD-built models. Most notable are the headlight configurations. The biggest giveaway is the rear light. GMD SD40-2s have a single beam, where EMD has twin-beam styled lights, usually placed next to each other. GMD models also have lights mounted on the nose, and EMD is above the cab between the numberboards. Some EMD variations have a nose headlight, although the headlight style and placement usually isn't the same as seen on the GMDs. Other features on the GMD models include the bell mounted above the cab between the numbers, triple-style classification lights above the numbers (since trains don't use classlights anymore, many locomotives have had them removed), and no numberboards on the back.