Important Details when Using Rod End Bearings #4
–The Witness Hole
Many rod end bearings have tiny holes at the base of their body, this is the witness hole. Its purpose is to allow you to easily check whether you have enough threads inserted into the body for a full strength connection.
Check to see daylight through. Or better yet push a piece of safety wire in and see if it comes out the other end. If the hole seems blocked, it means you have screwed in enough thread and you are good to go. If your rod end bearing has no hole, you may need to disassemble and look and see how deep the body is internally threaded and make sure that you use all of those threads when assembling for full strength.