(ECONOMICAL MODEL) Specification of this Portable Wheatstone Bridge is equivalent to Cat. No. 975 except resistance dials are made of 1% metal film, carbon resistance instead of Constantan or Manganin Coil. Rest all the features like series arm (4 decades), range multipliers (7 ranges), Battery, Push Buttons & Galvanometers are exactly same as in Cat. No. 975 Accuracy : ±2%