We have double hung vinyl, tilt out windows installed by the previous owners in 2004.The only number we were able to find was NAMI NFRC 100/200. We haven't been able to raise one of the lower set of windows. We removed both of the sashes and found that the balance plastic piece used to attach the spring is broken, same with the lower mechanism. We certainly need your advice and parts replacement. We live in Asheville, North Carolina 28803, and hope there is a dealer nearby, or that you are able to ship us two entirely new sashes. Most appreciatively, Mary
PS Looking at the window track it was removed from, we will definitely need your expertise in installing the two new sashes!