Cov Khoom Tshwj Xeeb Cov Roj Hmab Ua Khoom Siv Ua
-
Alloy Sib Tsoo thiab Grooving Log
Daim Ntawv Thov:Rau roj hmab cov menyuam sib tsoo los yog grooving cov txheej txheem nrog tag nrho ntawm hardness los ntawm kev xaiv cov thooj phiaj thiab tshwj xeeb.
