I've seen videos of people cutting down and repairing an air mattress/pad with an iron.
How about joining two pads with an iron? anyone done it.
For example taking two 66" long womens sized thermarest mattresses and using an iron to join them lengthwise for a 66" x 40" mattress that would weigh in around 24 ounces and no need for the extra weight of a Duo Coupler.
You would lose two independent pads in return for a duo mattress with two independent sides, something like the synmat exped duo hl only 6" shorter and less weight.
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