8级外六角螺栓加长螺丝m36m39m42m45m48m52m56m60m64 m30*50mm-800mm

8级外六角螺栓加长螺丝m36m39m42m45m48m52m56m60m64

大型加长特大高强度六角螺栓 42m48m52m56 m60m64m68m72大螺丝 42*150

m45m48m52m56m60m64m72m76m80m90特大高强度螺栓加长外六角螺丝

din912名义直径6mm的螺栓光杆部分尺寸在什么范围?急