【日本科学技术】钢珠球的制作流程【Japan Science and Technology 】Steel ball - Duration: 13:08. by Xman19870730 307,757 views 13:08 Play next Play now 2011年機械展-彈簧製作 - Duration: 2:46. by 六聖府 49,064 views 2:46 Play next
www.youtube.com