300900，秒速20%涨停，A股这一板块批量封板

Group 1: Defense and Military Industry - The defense and military sector has experienced a significant surge, with stocks like Guanglian Aviation (300900) hitting a 20% limit up [1][3] - The sector index has reached a new 10-year high, driven by strong performances from various sub-sectors including aerospace and military electronics [3][5] - Geopolitical tensions are escalating, with the U.S. increasing military presence in the Caribbean and announcing plans for new warships, which may further boost the defense sector [5][6] Group 2: Robotics Industry - The robotics industry is witnessing a collective rise, particularly in humanoid robots, with multiple stocks hitting their daily limit up [8][10] - UBTECH announced plans to acquire approximately 43% of Fenglong Co., with a total transaction value of 1.665 billion yuan, leading to a limit up for Fenglong upon resumption of trading [10] - Tesla's humanoid robot, Optimus, is progressing towards mass production, with plans for a million-unit capacity by the end of 2026, indicating a pivotal year for the humanoid robot market in 2025 [11]