At Paradigm, we are positively passionate about puzzles. Is your person an architect, engineer, or just inherently analytical? Perfecto! This is the perfect gift for them. Based on classical mechanics Newton's A-law clockwork and clockwork hooks provide energy to complete the power output without a battery, one winding can accurately run for 4 hours. No glue, tape, or tools required. Finished size 17" x 2.4" x 3.6". For ages 14 and up. Assembled Size: 9.5"L x 4.5"D x 13.8"H