Ziplock Bag as an Envelope

I've seen many different types of envelopes but I was still surprised when I received this corporate gift in an envelope that is actually a ziplock bag!


I guess this choice of an 'envelope paper' is in sync with the corporate gift's message of 'keeping your ideas fresh'. Very innovative.

Wonder how did they manage to persuade SingPost to accept this ziplock bag as an envelope for mail processing. Hmm.