Cov lus piav qhia luv luv:

U-bolt, tseem hu ua u-daim npav. Ib lub ntsia liaj qhov rooj feem ntau siv hauv cov yeeb nkab txhawm rau txhim kho cov kav dej. Lub bolt no zoo li tus duab U-puab. Siv los txuas ob firmware. Muaj 4.8 qib, 8.8 qib, 10.9 qib thiab 12.9 qib. Qhov kub-dip galvanized U-bolt yog U-bolt tom qab kub-dip galvanized saum npoo kev kho mob, yog li ua tiav cov nyhuv los tiv thaiv xeb.