"fastener is a mechanical device that is used to tie two objects together. such as a bolt,nail,rivet or screw " Which of the following doesn't belong to “紧固件” ?
A.螺栓
B.铆钉
C.螺钉
D.交换器
正确答案是D
"fastener is a mechanical device that is used to tie two objects together. such as a bolt,nail,rivet or screw " Which of the following doesn't belong to “紧固件” ?
A.螺栓
B.铆钉
C.螺钉
D.交换器
正确答案是D