自拍偷拍一区_日韩91视频_东凛在线观看_日韩欧美久久_亚洲h_男女做受视频_中文字幕一区二区三区乱码_丝袜诱惑一区_欧美一区二区黄片_狠狠狠狠狠狠狠狠_健身教练巨大粗爽gay视频_欧美六十路_国产免费观看视频_亚洲国产精品成人va在线观看_青青草原一区二区

The 1. diameter is 0.1-1mm (100 micron to 1000 micron), and the particle size range can be adjusted.

2. uniform particle size distribution

3. good sphericity.

4. solid ball with smooth surface and good fluidity.

5. there is no concave and convex shape on the surface.

6. Qiao Feng patent product

7., especially for lead, bitumen, other metal materials, ceramic materials.