Matching Bearing 23693 and 23694 (THK)
Grease Nipples are added onto bearings to allow for proper greasing. Well greased bearings run better and smoother.
It is vital that you maintain your machine by regular greasing of the bearings and ball screws.
Grease Nipples (or fittings) can be damaged by getting plugged or simply broken off. Immediately replace damaged nipples as grease will be lost through the broken part.