Valavu yokhala ndi magawo awiri anjira zitatu ndi valavu yobwerera yokhala ndi malo awiri ndi madoko atatu opangira ma pneumatic.Pali mitundu yambiri ya iwo, ndipo iwo akhoza kugawidwa mu mavavu kulamulira magetsi, valavu kulamulira mpweya, mavavu kulamulira makina, valavu kulamulira Buku, mavavu phazi ndi zina zotero...
Werengani zambiri