When the envelopes arrived, I tested them.  I pulled an envelope from the box and did my best to seal it by rubbing the seal under pressure.  I was able to open the envelope easily, as if they were made to be reopened.  I tried again with another envelope, this time leaving it sealed for an hour to see if the adhesive would stick better over time.  I was able to open it as easily as before.

I noticed that the blue security printing inside the envelope had a simple pattern, and I wondered how hard it would be to read a check that was sealed inside.  I inserted a check, sealed the flaps and held the envelope up to a small (4" diameter) fluorescent desk lamp.  I could read every word and number on the check as easily as if the envelope had no security printing.

At minimum, a security envelope should seal securely and make it very difficult if not impossible to read the writing on a check sealed inside.  The Columbian CO284 security envelopes fails this standard completely.  Next time I'll stick to my gold standard.  Mead security envelopes with adhesive that requires dampening to seal.  Unfortunately Mead's self-stick envelopes don't seal well enough either, and the paper they're made of is much too thin and flimsy.
When the envelopes arrived, I tested them. I pulled an envelope from the box and did my best to seal it by rubbing the seal under pressure. I was able to open the envelope easily, as if they were made to be reopened. I tried again with another envelope, this time leaving it sealed for an hour to see if the adhesive would stick better over time. I was able to open it as easily as before. I noticed that the blue security printing inside the envelope had a simple pattern, and I wondered how hard it would be to read a check that was sealed inside. I inserted a check, sealed the flaps and held the envelope up to a small (4" diameter) fluorescent desk lamp. I could read every word and number on the check as easily as if the envelope had no security printing. At minimum, a security envelope should seal securely and make it very difficult if not impossible to read the writing on a check sealed inside. The Columbian CO284 security envelopes fails this standard completely. Next time I'll stick to my gold standard. Mead security envelopes with adhesive that requires dampening to seal. Unfortunately Mead's self-stick envelopes don't seal well enough either, and the paper they're made of is much too thin and flimsy.