Rail-to-Road Aggregate Transfer Kit HO ScaleWalthers Cornerstone Rail to Road Aggregate Transfer KIt 14 1 2 x 9 5 8 x 11" 36. 8 x 24. 4 x 27. 9cm HO Scale Walthers Cornerstone #: 933 4036 One of the newest industries along the rails involves some of the oldest material on earth sand! While it's been used for centuries to make building materials, glass and metal castings, you'll also find it in paint, fertilizer and plastics. Recently, fracturing sand} (or frac sand}) has become a hot commodity,