Abstract: Equipment for testing materials for the effects of stress corrosion cracking, which includes more than two tensioning units, each consisting of a base plate, two guide bars, an upper and a lower cross-beam, a locking system for the guide of the lower cross-beam and a connecting flange between the cross-beam and a threaded bar for causing elongation of a test sample. The power drive supply block drives the threaded bar. A motor power unit is included in the power drive supply block and vertically-slippable gearing is inserted between the motor gearing and the block. The motor power unit consists of two stepping motors driving sun gears. The sun gears drive planetary gears which, by means of an arm, drive the drive shaft operatively associated with the threaded bar. In particular, the invention relates to equipment with six tensioning units comprising an automatic limit switch-off means and a lift system in the power drive supply block for separating the drive gears from the rest of the system.