Pair of calibrated jet gauges 

1 - 0.45 - 1.50mm  (.45 to 1.30 in .05 increments & 1.40, 1.50)  (16 sizes)

2 - 1.5 - 3.0mm (in 0.10 increments)  (16 sizes)

German manufactured and to exact tolerances

A must have for any serious carburettor tuner.