47:30
The process of processing a large block of iron into a king bolt
1:58:51
Why Millions Are Obsessed With These 5 Satisfying Factory Processes
44:52
【ベスト５】日本が世界に誇る真似できない職人技！驚異と衝撃の技術！
24:49
Amazing Bulldozer Mass Production Process! Impressive Modern Factory！
25:34