This was Omegas first electronic chronometer. Known as the sand pile or cone due to its unusual shape, this watch is also distinctive in that it was originally water-resistand to 60-metres (but dont wear it in the shower now!) and it housed the iconic Omega 1260 "hummer" calibre. Called that because it hums and does so because it has a vibrating tuning fork inside powered by a battery. It vibrates at 300 (hence f300 Hz on the dial) times per second and when manufactured was accurate to 60 seconds per month - and it still is! Bullet-proof engineering, this is a heavy watch at 108gms. The stainless steel case is in overall good condition with numerous minor dings and scratches.  The case back is signed Omega and has the Omega sea monster in crisp relief. Omega signed crown for adjusting the time, day and date. The silver dial is good although a little patchy through age. Silver baton hands partly finished in deep black. Red sweep seconds hand. Applied hour batons. Fully functional day and date at 3. Signed Seamaster Chronometer and below is the applied Omega script and signed Electronic f300Hz. At 12 is the applied Omega logo set in red, so identifying it as an f300. Mineral crystal has scratches. Comes with the original Omega stainless steel bracelet. Please note the electronic movement is NOT covered by the guarantee.