Unlike today, during the 1960s Heuer used to specialize in far more than watches - to include stopwatches for sports timing, yachting, science and research (like the example here), automotive, aircraft, and far more.
Heuer stopwatches were designed to measure everything from 1/5th a second to 1/100th of a second, like the example here - a new-old stock (NOS) 1970s Ref. 570 1/100 split minute recorder stopwatch - which measures 1/100 minute (decimal) with split action with a 0-30 jumping minute register and comes with its original Heuer box, instructions manual, and warranty paperwork.
Per Heuer literature of the era, the 1/100th minute stopwatches were most frequently used for measurements in laboratories, research, and sport - and particularly humorous (per the same literature), some Heuer stopwatches were recommended for use by...DJs.
Perhaps less hilarious, some were also issued to the USG's Office of Civilian Defense, the predecessor of the Federal Emergency Management Agency (FEMA).
Within North Atlantic Treaty Organization (NATO) member states – to include the U.S. – starting in the 1950s, Civilian Defense organizations (all of which used the same triangle “CD” logo, with some European countries continuing to use it to this day) were tasked with preparing for the aftermath of a nuclear war between NATO and the Soviet Union, which seemed likely during the Cold War.
This Heuer stopwatch comes with a rugged travel case, and its original box & papers.
New Old Stock 1970s Heuer Ref. 570 1/100 Split Minute Stopwatch, w/Box & Papers
DIAL: NOS condition Heuer-signed white dial, with highly visible yellow 30-minute subdial register and correct handset.
CASE: Black 58.5mm x 74mm (to include center stopwatch pusher) case; caseback retains its original Heuer sticker, replete with crisply legible writing. Case is in NOS condition.
CRYSTAL: No scratches nor cracks.
MOVEMENT: "Shockprotected" 15-jewel Heuer manual mechanical movement. Events measured were timed up to 30 minutes. Operations are via a central crown, with start, stop, and return to zero by successive depressions of the crown, lending to simple time measurements, for example the duration of chemical reactions, track timing, etc.
CROWN: Unsigned crown; minute and second hand reset pusher.
This Heuer Ref. 570 split minute stopwatch comes with its original Heuer box, instructions manual, and warranty paperwork.