I have never used safe-T mailers or any bubble wrap protection when I ship chips first class mail. When I sell an item with a shipping charge of $3.50 to $5.00, then my approach is entirely different. But, if I'm selling a chip for a few dollars and only charging $1.00 to $1.50 shipping, I send it first class mail as I described earlier. I suppose I'll have to change my ways, but for over 10 years (until the other day), my system has worked fine for me without damage or loss issues. I'm not arguing that my way is the right way, I'm only saying that I've not run into issues in the past. I realize I will likely have to adjust. I have a meeting with the post office on Monday and hope to get further clarification from them as to what options they find acceptable and what options they don't.
Joe
PS - I also check every envelope for weight and thickness when shipping first class.