I got my Blink installed yesterday. The tech said that it's supposed to come with a lock/seal/tag to prevent owners from opening up the unit and mess around inside. He said if you need service and they don't see it on your unit, they're going to assume that you broke the lock/seal off and may refuse servicing the unit because it could have been already tampered with by the owner. He said he'd give me a confirmation paperwork in writing from him that the unit doesn't come with a lock.
But then he forgot to give it to me at the end when he was done and I forgot to ask. I had to send him an email to ask him to send it to me when he sends me the permit paperwork.
I wonder how many other people's Blink units come with a lock/seal.