Our upstairs bedroom windows faces our neighbors house not 15ft away. With the interstate nearby, sometimes the highway noise echoes between the houses and creates a really noisy situation. The two window inserts have literally cut the noise down to almost nothing which was a huge surprise. Not only that it just seems more cozy as well. The laser measure kit was a must as we had to fit the inserts in between the plantation shudders' brackets with no room to spare... perfect fit!