round head square-neck bolt 圆头方颈螺栓

oval head square neck bolt 椭圆头方颈螺栓

cup head square neck bolt 半圆头方颈螺栓

cup square neck bolt 马车螺栓

countersunk square neck bolt 埋头方颈螺栓

round-head short square-neck bolt 圆头短方颈螺栓

countersunk head square neck bolt 沉头方颈螺栓

square neck bolt west bank 方镇螺栓

half-round head square neck bolt 半圆头方颈螺栓