... cableFor laying indoors,in tunnel, cable trench,or direct in ground,able to bear external mechanical forces.but unable to bear ... laying indoors,in tunnel, cable trench,well or direct in ground,able to bear external mechanical forces and Determinate pulling force ... 1 5.0 Acceptable Brinell Hardness Tester HB-3000C 1 5.0 Acceptable DC Digital Resistance Tester SB2230 1 5.0 Acceptable DC ...