This is not a new idea per se, but then again do you know that most if not all re-usable envelopes were not approved by the USPS. This means that chanves are your letter would get delayed along the way or returned (the letters need to be machinable thus pertaining to standard dimensions). Ecoenvelopes has the credit of producing the first such re-usable envelopes that are approved.

Lets just hope for Ma Natures sakes that the idea works. If you are wondering , how useful it would be and would it have an impact then have a look at this:

Eliminating return envelopes saves energy, water, and forest resources and reduces the carbon emissions that contribute to climate change. Every one million ecoEnvelopes used saves an estimated 250 million BTUs of energy and 37,000 pounds of greenhouse gasses. All ecoEnvelopes are manufactured on certified papers from managed forests using up to 100% recycled content.

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