The Wilson Vari-Rest WHVREST is a fixture for testing elongated parts. The fixture is clamped to the top of the elevating screw or base adapter and adjusted to properly support and bring elongated test piece into correct relationship with the anvil and indenter. Distance from center of elevating screw to end of support tube - 635 mm (25 in). Fits all Wilson lead screw, 574 and 2003 hardness testers.