Laboratory standard d.c. (moving-coil) ammeter with 12 inch scale, model S.66 No. AA4209, by Sangamo Weston Ltd., Enfield, Middlesex, England. 10mA movement dropping 50mV (at terminals of leads), accurate to 0.1% of full scale, for use with external shunts. Fitted with levelling feet and built-in spirit level and mercury thermometer. With connecting leads, and printed calibration certificate dated 11 February 1953