The Torsion Apparatus (Searle's or Barton's) features a sturdy steel frame on a cast iron base with leveling screws. It includes a 900mm long, 5mm diameter test rod secured by a 3-jaw chuck at the top and a torsional drum at the bottom, which can be rotated using scale pans and frictionless pulleys. Three graduated circular scales with clamps and three pointers are provided for precise measurements. The set includes three additional rods, strings, and two scale pans (weights not
included).