Otu n'ime ndị na-emepụta China nke Hexagon Head Flange Face Bolts, na-enye ọmarịcha mma na ọnụahịa asọmpi, bụ DONGSHAO. Nke a bụ ụdị bolt a na-ejikarị eme ihe n'ọtụtụ ụlọ ọrụ mmepụta ihe na nke obodo. Ọ nwere nkọwapụta eri nke M8 × 1-M16 × 1.5, eriri dị mma, akara arụmọrụ nke 8.89.810.912.9 na A2-70, yana ọkwa ngwaahịa A.
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