Sib sib zog nqus cov groove pob bearings yog ntau siv. Ib tug sib sib zog nqus zawj yog tsim nyob rau txhua lub puab thiab sab nraud uas muaj kev coj mus muag rau lawv raws li kev sib koom ua ke uas ua rau muaj kev sib xyaw ua ke ntawm cov rog no. Sib sib zog nqus cov groove pob bearings yog haum rau kev siv daim ntaub ntawv siab. Ntxiv nrog rau hom qhib, sib sib zog nqus groove pob bearings tuaj nyob rau hauv ib tug lossis ob sab ris, bearings nrog snap rings thiab muaj peev txheej muaj peev xwm tshwj xeeb, thiab lwm yam.