180224-N-SH284-0047 KEYPORT, Wash. (Feb. 24, 2018) Aviation Boatswain's Mate 1st Class Mark Dalmacio, assigned to Naval Base Kitsap, demonstrates how a 3D printer works during the Naval Undersea Museum-Keyport's 20th annual Discover "E" Day. Discover "E" Day is a national event designed to engage the young people of our nation in science, technology, engineering, and mathematics (STEM) learning and inspire them to future careers in those fields. (U.S. Navy photo by Mass Communication Specialist 2nd Class Vaughan Dill/Released)