These are optional Blue Aluminum Stabilizer Ball Ends.
These connect the sway bar to the vehicle.

FEATURES: Blue anodized aluminum construction

INCLUDES: Four 4.8mm stabilizer ends
Four 3x4mm set screws

REQUIRES: Installation onto vehicle.

COMMENTS: These stabilizer ends work on the following vehicles, but not
limited to this list: TRF414M, TB-EVO I, II, III, or any vehicle
equipped with the stabilizer bar sets 53441, 53442, 53467, 53517,
and 53611.