Nws yog siv rau qhov me me lossis cylindrical qhov ntawm nqua, xws li txhais tes, ko taw, dab teg thiab hauv pliaj, thiab tseem rau thaum pib ntawm ntau yam hnav. Dov daim ntaub qhwv lub txav sab saud, tuav nws sab tes xis thiab nthuav daim ntaub qhwv ntev li 8cm, kho lub taub hau kawg ntawm daim ntaub qhwv nrog koj tus ntiv tes laug, thiab qhwv ib ntu hauv cov nplhaib txuas ntxiv nrog koj sab tes xis. Tus naj npawb ntawm yob nyob ntawm koj xav tau. Kho qhov kawg ntawm cov ntaub qhwv nrog cov ntaub qhwv nyias.
