Model: Single Red Submariner Reference: 1680 Date: Circa 1974 Movement: 26-jewel Cal.1570 automatic, free-sprung Glucydur balance, adjusted to 5 positions, No.D650850 Dial: Black, red Submariner, luminous dot hour markers, baton quarters, white outer minute divisions, magnified date aperture at 3, polished Mercedes hands with luminous inserts, polished centre seconds Case: Brushed and polished tonneau form, screw down back, shouldered screw down crown, bi-directional bezel with black calibrated bezel, No.3695439 Strap/Bracelet: Brushed 93150 Oyster link Buckle/Clasp: Signed folding clasp, stamped X10 Signed: Case, dial & movement Size: 40mm Accompaniments: Rolex box, spare link 注脚 Production of the reference 1680 first began in 1966 and was the first Submariner to feature a date function. The earliest of these models had the depth rating with meters positioned first, followed by feet rating. For over a decade the word 'Submariner' was depicted in red on the dial of the 1680 and as such has since earned the nickname of a 'Single Red Submariner'.