It is clear that no one is waiting for these letters, no one asked to receive them, and therefore few people will open and read them. But as I know that users disapprove of this marketing ploy, because for many people such letters are like spam. On how to grammatically implement this system in your company you can learn from https://www.growbots.com/blog/effective-cold-email-opening-lines/. I think it will be useful for you to read their methods.

But it can actually do you a lot of good: provided you do it right, of course. Clearly, cold emails cannot replace the benefits of inbound marketing, but as an additional way to stimulate growth in the short term while inbound campaigns are gaining momentum, they are very good.