Abstract: A speed and/or distance transducer is mounted in a bolt-shaped hollow housing and is threaded into a transmission and locked in place with its detector and adjacent a toothed wheel which rotates to produce an electrical output. An indicia is provided on the head of the bolt to allow proper spacing of the end of the transducer relative to the toothed wheel. A divider converts the output of the detector and a switch with a rotary member can be accessed through a bolt opening to allow the divider ratio to be changed. A plug covers the opening after the dividing ratio has been selected.