This roadbed is designed with a more realistic 30-degree slopes found in many  actual  railroad roadbeds.  The scale dimensions are  12" high.  Actual dimensions are  4.5 mm thick (approx. 3/16"), 3.8 cm across the top (approx. 1-7/16" ), 5.15cm across the bottom (2-1/8") and 32" long.  Minimum radius for the bendable products is 18".  Roadbed is sold in 8' bundles.  You receive a bundle of 6 strips, 32" long for each 8' of roadbed ordered.  Roadbed is in halves, so 6 pieces make 96" or 8' of roadbed.  This roadbed is designed so that laying it side to side will yield 2-1/8" track centers.