● Kev teeb tsa yooj yim vim muaj cov khoom siv tsawg dua
● Lub load faib ntawm plaub-kab rollers yog txhim kho kom txo tau hnav thiab ua kom lub neej ua haujlwm ntev
● Vim qhov txo qis ntawm lub nplhaib sab hauv qhov dav, qhov axial positioning ntawm lub caj dab yob yog yooj yim.