This is the left side of the miniature filming model "window" for the Enterprises landing bay. Model made by Greg Jein and aquired by Anthony Fredrickson. 27" long.
Small excerpt about it from Wikipedia:
Star Trek V: The Final Frontier featured many scenes of an updated shuttlecraft, also sporting the name Galileo. The design was similar in size and shape to the original series shuttle, with updated engine nacelles and a large rear hatch. The miniature shuttle and landing bay were built by Greg Jein. The Shuttle was also built as a full-sized prop berthed in a full-scale hangar deck set.
