Customs could just ask you for a declaration, where if you lied and they found out later, you'd suffer a heavier penalty. I dont know if they do that right now (not familiar with it).
>>chii+(OP)
What would they found? I have ordered screwdriver SN-2249. Customs sees screwdriver SN-2249 on manifest and on invoice. What that screwdriver is used for? For tightening and loosing screws, duh. In no step of the process I have lied.