What makes the Progress a "Hybrid" stove?

This question has been the most commonly fielded questions thus far about our new stove.  Below is an explanation of just what we mean by "hybrid". 

Progress Hybrid Introductory Pricing & Availablilty

We will introduce the Progress Hybrid at our Open House on October 7 & 8, 2011 and then plan to begin shipping during the last week in October. We are offering great introductory pricing-