Here is a great little tachometer for your lathe or mill that reads out surface feet/minute. That's right, you get accurate rpm measurements from as low as 3 up to 9999 (± 1) rpm plus you can enter the diameter of the work piece or cutting tool or your bandsaw wheel size via the rotary encoder and the tach will display the surface feet/minute (or meters/minute) for any rpm. Just adjust the rpm of your machine to get the desired SFM. Works great on wood or metal lathes, mills, drill presses, bandsaws, conveyors, etc. Instantly switch from rpm to sfm at the touch of a button. Large, easy to read 9/16" tall filtered bright Red 4 digit readout. LEDs tell which function is being displayed. Dip switch lets you select from 1 to 16 marks per revolution for the optical sensor. Mark your pulley, spindle, collar or anything that turns at spindle speed. The sensor has a built in IR light source so it will work inside a belt cover or headstock. There is a sensor sensitivity adjustment on the circuit board so you can adjust for optimal reading without going back and physically moving the sensor. Mounting is easy with small screws or double faced foam tape. The tach is designed and manufactured by Trexon,Inc. in Canada. It is a robust and stable microprocessor based circuit and units have been in service for over 10 years with no problems reported. It will pay for itself in convenience and man hours saved, not to mention getting better finishes and the most life out of your expensive cutting tools buy cutting at the recommended surface feet per minute for each application. Operates on any 9 to 12 volt dc power source. Power transformer is included with all models in housings. Extra optical sensors available for those with 3 in 1 machines or other multiple applications. PC board and firmware copyrighted. All units come with 1 year factory warranty. See the links above for mounting examples and ordering information.