For the people who like to print on glass, but not to permanently modify their Replicator. This Left bearing allows the use of a glass clip to toggle between glass or the standard base plate. The original left bearing as designed by botteworks is the same height as the back wooden cross piece which did not leave room for any clip to be attached to the back of the build platform. By deleting a portion of the left bearing you now have room to attach any size clip you want.Note: The picture of the Left Bearing was printed before the Aluminum HBP Arms upgrade.ABS Plastic15% Infill/Octagon Pattern. .27mm layer height. I printed on Glass with full support, but with NO raft.