The Warp Delta was a United Earth Ship that appeared in the opening titles of every episode of STAR TREK: ENTERPRISE. It was designed as a ship that could bridge the gap between Zefram Cochrane's Phoenix and Captain Arhers Enterprise NX-01. The ship was never given a formal name but also appeared in the episode 'The Expanse', where it was attacked by a Klingon bird-of-prey. The model is just over 4" (10.5 cm) long.