Yes it does. On mine which is the Hydro stat, its on the left hand side towards the bottom of the platform. You use your left heal to engage it by stepping on it. After you are done, lift your foot off and you are back to normal.
My XG3025 with shuttle shift transmission does have it. On my tractor, it's located close to the platform on the right side, To engage press it down with your heal and to disengage just let up. It's come in real handy on a few occasions.