A.a->b->d->c B.b->a->c->d C.d->a->b->c D.a->d->b->c
A.12*6mm B.1.2*0.6Inch C.0.12*0.06Inch D.0.12*0.6Inch
A.PCBB.PCBAC.PCAD.以上都不對(duì)