Longacre® 52-44391 AccuTech® Digital Tachometer - 10K

It is ultra light and weighs only about 1-1/2 ounces Use of state of the art electronics give you accuracy to within 10 RPM Includes mounting bracket that also helps protect tach from damage The tach function is self-powered (battery lasts 300+ hours) Comes with a high RPM warning light which helps prevent accidental over revving of expensive motors