Shore durometer B, C, D, DO, E, M, O, OO, OOO, OOO-S, and R. Each scale results in a value between 0 and 100, with higher values indicating a harder material. Durometer, like many other hardness tests, measures the depth of an indentation in the material created by a given force on a standardized presser foot. This depth is dependent on the hardness of the material, its viscoelastic properties, the shape of the presser foot, and the duration of the test. ASTM D2240 durometers allows for a measurement of the initial hardness, or the indentation hardness after a given period of time.
Michigan Shore-to-Shore Trail Michigan Shore-to-Shore Trail The Michigan Shore-to-Shore Trail (also known as the Michigan Riding and Hiking Trail) is a trail that runs between Empire on Lake Michigan and Oscoda on Lake Huron across the Lower Peninsula of Michigan. It is open to horseback riders and hikers but not bicycles. The trail's western end is located within the Sleeping Bear Dunes National Lakeshore. The trail, going from west to east, travels through the Boardman River valley and follows the Au Sable River for about . The trail was developed by trail riders in 1962 and travels through mixed hardwood and conifer forests.