In this March 4, 2011 photo, a Check Valve Adapter …
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Toby Talbot | published: March 7, 2011

In this March 4, 2011 photo, a Check Valve Adapter is seen with a bottle of maple syrup in East Montpelier, Vt. The device was developed by maple researchers at the University of Vermont as a means of extending the six-week sugaring season. (AP Photo/Toby Talbot)