Renault FT
The Renault FT was a type of World War I tank seen in the resetting time stream, after Captain Jonathan Archer and the cew of  had managed to restore it. ()

The same type of tanks were also used in the mirror universe on Earth during a conflict in an otherwise unspecified period of time in its history. ( opening credits)

Appendices

Background information 
Although not mentioned by name in either episode, the appearance of the Renault FT in the opening credits, indicated that the vehicle was manufactured and used in the mirror universe as well.

Both clippings originated from the 1927 Paramount Pictures silent – as in no dialog – World War I aviation film Wings (the very first "Best Picture" Academy Award winner), and are in effect one and the same, albeit flipped – or "mirrored" if you will. Shot on location near San Antonio, Texas, the Star Trek-used clipping with the Renault FT tanks was part of a larger sequence depicting the 1918 , which was originally included on a 1985/1989 reissue version of the film released on VHS by Paramount Home Video, from which the Enterprise producers lifted the clippings for use in the series, cleaned-up and hue corrected in post-editing to match the rest of their respective chronology sequences. It was trimmed though from the already extensive Battle of Saint-Mihiel sequence on the 2012 remastered release.  This restored and remastered version was released on the occasion of the studio's 100th anniversary and the film's 85th, and on which Ben Burtt had worked as restoring sound (effects) editor. 

The tanks shown, actually concerned the American made  standing in for its French original, the Renault FT tank.  Being licensed built copies, production only started in 1918, and none reached the frontlines during World War I, the American forces instead using the French originals.

External link
 

Mirror universe
Earth vehicles
Ground vehicles