Fill unused holes on fixture plates and columns to keep chips and shavings from clogging or damaging them. These plugs are easy to install and remove, so you can switch them to a different hole when you need to change setups.

Install screw-in plugs into threaded holes with a screwdriver. They have a slotted drive that resists chip buildup. Black-oxide steel plugs are the most durable, so they’re good for repeated use in demanding applications. The black oxide coating provides mild corrosion resistance. Aluminum plugs are more corrosion resistant than steel plugs—they’re also gentler on steel threads. Plastic plugs are lightweight and economical.