These are black oxide coated steel slotted posts. They are used for mounting sheath and holster attachments. Because they are slotted, they can be easily tightened or removed. Some users also like to reverse their mountings to make the attachment more secure. These will fit any screw with an 8-32 thread.
1 package = 10 slotted posts
Black Oxide Coated
.375 barrel length (under head)
.20 barrel diameter
.415 head diameter