螺絲，攻牙 M2.9x9.5 圓頭十字槽

Was a little worried the M2.9 threads would strip, but they bit perfectly into the filter box holes on my SC4 lathe. The round head sits flush and looks clean.

Found the exact match for the SC4 bench lathe's filter box screw, and the self-tapping threads bit into the aluminum cleanly without any pilot hole fuss. The round head sits flush enough that the cover closes properly now, and the Phillips drive didn't strip even under firm torque.

The threads are clean and sharp, so they bit into the metal without much effort. Used a few to secure the filter box on my lathe and they held tight without stripping. Happy with this pack for getting the old machine back together.