Best cold wallet

What is the consensus on the best cold storage wallet?

And additional, VERY, important question:

Is it possible that someone with ill intent, say a company, could install/add some sort of software/thing to the actual cold storage before it is sent out to me, in a way that they could hack and retrieve all BTC / ETH, through a switch? Or through activating whatever they installed? As you may notice, not the most familiar atm, but i am hopeful you get the direction I’m coming from with the question.