precision tool/instrument
From Longman Dictionary of Contemporary Englishprecision tool/instrumentprecision tool/instrumentTZa precision tool or instrument is used for making or measuring something in a very exact way → precisionExamples from the Corpusprecision tool/instrument• Basingstoke is noted for precision instruments.• Wildland fire is not a precision instrument.• A precision instrument whose chief virtues were useless to anyone in this age.