An identification device comprising an ultrasound transmitter unit and an outer housing which receives said transmitter unit, said outer housing comprising one or more apertures which are sealed by a membrane, said membrane being substantially transparent to ultrasound when compared to the rest of the housing. Control includes calculation of a regeneration current and comparison of the regeneration current to battery current to calculate the surplus regeneration power. On engine thrust being increased, compressor output also increases and rapidly flexes casing radially outwards, thus equally rapidly moving the segments away from the tips of the turbine blades. chemical formula 1 In the formula, R1 represents a group having 4-20 carbon atoms in total and a substituent having a formula weight or 70-350 : R2R4 independently represent a substituent; n2 represents a number of 0-4; n3 represents a number of 0-2; n4 represents a number of 0-8; and Q represents an atomic group necessary for forming an aromatic hydrocarbon ring or an aromatic heterocyclic ring. The salt of the hydroxynitrobenzodifuroxan of this compound is useful in explosive compositions.