Thrust bearing for mast diameter up to 50 mm, with 4 bolts for the installation. The bearing can be used without platform with the tie rods (see photo); The safety ring for attachment to the guys and is supplied with the GS-050. Small metal parts to prevent damage to the mast protection when you fix the installation screws. Mechanical installation is as for model GS-680U, but the mast diameter just up to 66 mm. It does not fit in the rotor platform!