av永久免费观看,日韩在线精品视频,在线观看国产视频,国产精品久久片,国产毛片av网站,国产又粗又硬又黄又刺激,国产黄色片视频

Main Products
Products Grade: Y3Cr13、420F
Specifications: φ5.5-38mm
Applied Standard:  Agreement
Characteristics: Shaft products
Applications: free-cutting stainless steel
Use of Products: Steel to improve the machinability of 3Cr13.