isingeniso esifushane
Imikhiqizo yase-Japan ingahlukaniswa ngemikhiqizo ye-tubular kanye nemikhiqizo engeyona i-tubular (okungukuthi, isigaba a kanye nemikhiqizo yesigaba b).I-PSE Mark iyimpoqo emikhiqizweni elawulwayo, futhi u-s-mark uyazikhethela emikhiqizweni engalawulwa.
