The 8008 Resistivity Chamber is a guarded test fixture for measuring volume and surface resis- tivities. It assures good electrostatic shielding and high insulation resistance up to 1100V. The 8008 accommodates sheet samples 64 to 102mm (21?2 to 4 in) in diameter and up to 3.2mm (1?8 in) thick. It maintains good sample con- tact with uniform 1 pound pressure on smooth parallel samples. A lid switch activates the voltage disable input on the rear panel of the 487 or SMU. The 8008 permits direct measurement of volume resistivity up to 1018?-cm (on samples 0.1cm thick) and surface resistivity up to 1017?/square in accordance with ASTM procedures.