Physical description
Dial and four digit indicator to calculate revolutions of a moving part (such as an engine or shaft). In black box with red lining. Instructions sheets are included
Inscriptions & markings
Probator
"Directions for Use/ Speed Indicator Record/ Applicable up to 6000 rpm/ for spindles rotating clockwise and anticlockwise/ tests up to 1000 rpm may be made by the steel tip the pointed/ rubber tip should be used for higher speeds/ to reset the counter one turn of the knurled knob will be sufficient/ Do not Reset whilst the counter is in motion/ The instrument is to be lubricated from time to time with a good/ neatsfoot oil"
These instructions are repeated in other languages
