Stacks Chronotronic Tachometers Are Based Upon The Clubman Architecture With Styling And A Digital Stepper Motor Movement Designed To Faithfully Replicate The Original Chronometric Units, Whilst Retaining The Features And Precision Of A Modern Racing Tachometer. When Your Car Is Pitted Or Going Through Scrutineering It Will Look And Move As If It Were The Original Instrument. Under Race Conditions, However, Power The Vehicle Beyond The Factory Set Rpm Limit And The Needle Will Display And Move Like A Modern Tachometer To Give Precise Engine Speed Information For When You Need It Most.