First introduced in 1965, the Trimline included a lighted dial and was encased in a sleek, curved plastic housing that took up much less space than earlier Western Electric telephones. However, the glass-smooth and shallowly-curved plastic handset proved difficult to retain between cheek and shoulder for hands-free communication without slipping, and this problem was never corrected over the life of the model line. Cushioned clamp-on adaptors were manufactured and sold by third parties to make it easier to cradle the handset, but these add-ons would greatly compromise the aesthetic appearance of the telephone.