Triangular shape with reflective dome shape protrusions in echelon formation, from front to right side.

Was still up watching a movie and decided to step out onto the patio to have a smoke before going to bed. Was outside maybe 2 minutes when directly over head a large triangular craft passed over head about 300 feet AGL. Had three highly reflective dome shaped protrusions on bottom, in echelon formation from front to right, that I could see reflection of ground features in as it passed over head. I could see reflection of the treeline in our yard and the roof of the Walmart directly behind our house. As it continued moving South-South-East it made no sound and passed farther down range, I could see the height top to bottom, because of the ground lights at Walmart and the shopping mall. Moved slowly, approximately 10-20 mph to the SSE until out of view. Total viewing of 60-90 seconds before loosing sight of it in darkness.
I grew up around aircraft and always had a love of aircraft and flying. I am an Airframe and Powerplant mechanic, and know, and can identify all types of aircraft manufactured, both civilian and military. I know what I saw, and it was NOT an fixed or rotory wing aircraft, or dirigible.