Acquired two models for our entrance bedrooms as we are on a noisy major road. Put in them yesterday and the difference in noise is amazing. I went for the 6.4mm laminated glass and positioned the units to the entrance of your window sill to give maximum hole. We live https://extralargebanksycanvaspri36917.blog-ezine.com/26912408/slimline-secondary-glazing-chelsea-secrets