Restored original Smiths chronometric tachometer RC1307/01. 2-1 ratio. MINT condition. Not used since it was restored. Factory correct for 1963 Triumph T120 and TR6 twins. Perfect for that factory correct restoration when it has to be 100% for judging. Very  hard to find first year unit twin instrument. May work on other bikes? Any questions call me at 860-848-0607. I have dozens of smiths instruments available.