Vintage Royal purple glass insulator by Hemingray. Perfect for collectors or decor enthusiasts. The Hemingray-54 A&B is an uncommon two piece transposition style insulator. Transposition styles were used for swapping the positions of two lines. he Hemingray-54 A&B is an uncommon two piece transposition style insulator. Transposition styles were used for swapping the positions of two lines. This would reduce the interference that would otherwise be caused by two lines running parallel to each other for too long a distance. Both pieces are in perfect condition