The Olympics Games are knocking on the door. Behind all the anticipation of the games, who will bag what medal,  and the entertainment that will follow, is a factor that makes it or breaks it - the time taken.

Many sports require a timekeeping that must have split second precision. In the world of mechanical watches, this is where 'splitters' come in -- timepieces that 'split time'. A rattrapante, or split seconds, chronograph is the type of chronograph that has two seconds hands that help you time multiple simultaneous events. The rattrapante finds its genesis in the French word rattraper - to catch up or recapturing.

Understanding rattrapante 101

The rattrapante allows timekeepers to evaluate fastest and slowest lap times with utmost precision. The rattrapante hand can be triggered and instantly be called back to zero. Its genius lies in how this all can be done concurrently with the main chronograph hand. This mechanism is used with a pusher which immediately brings the rattrapante hand to fall in with the main chronograph hand.

A deeper dive into mechanism

Finding its roots in the 19th century - functioning inside pocket watches, the rattrapante chronograph has come a long way. And if you are wondering what makes it tick so precisely, then this can help you.

Sample this: There is a track event with three laps and you want to record all the different lap times - that is every time the athlete crosses the start-finish line. Stopping the chronograph is not an option. If the chronograph is stopped, it will stop recording the next lap.

Welcome splitters -- you need a split seconds timepiece that can record different lap times. Different movements are constructed differently but generally, it works like this: Different lap times are recorded with the help of the split-second chronograph hand that at the same time is activated by the chronograph second hand with the chronograph still running.

Now come the cams. FYI: A cam is used to reset the chronograph hand or activate the hammers in a minute-repeater.

The chronograph second hand turns the indented cam. A ruby roller on a lever is placed in that small indent. That lever is connected to the split-second wheel. A spring clutches this split-second wheel under tension and when the split-seconds wheel is released, the roller rests in the indented cam and gets triggered by the chronograph seconds, turning the split-second hand at the same time.

The cam continues to go around when the split-second wheel is fastened. Then, the sprung lever paves a way for the ruby roller to roll out of the indented cam and go around the cam. This continues to happen until the breaks are let go. When you release the brakes, the spring in the lever of the roller pushes the split-second wheel to go around with the shape of the cam. This sends back the cam to its notch resulting in the integration of the split-second hand back under the hand of the main chronograph. We mentioned above that different movements can work differently but in its essence, this is how a rattrapante works to be considered as one of the grand complications.

Here's a look at five rattrapante watches that make every millisecond count.

A. Lange & Söhne Triple Split  Ref. 424.037

Introduced this year, the  Triple Split  Ref. 424.037 in pink gold and blue dial is the younger sibling of the Triple Split in white gold that was released in 2018. The pink gold Tripple Split houses a dial crafted from solid silver; hands made of pink gold, rhodiumed gold, rhodiumed steel, and gold-plated steel.

Hailing from the Saxonia family, the pink gold Triple Split is driven by the Calibre L132.1 movement that comes housed in a 43.2mm case. Limited to 100 pieces, this timepiece offers a visual delight when turned around - the view of its movement visible through its sapphire caseback. The watch is offered on a dark blue leather strap with grey stitching and pink gold deployant buckle.

Patek Philipp 5204R Split-Seconds Chronograph, Perpetual Calendar

The 5204R is a timepiece of nxt level with split-seconds chronograph alongside the tourbillon and the minute repeater. Offering a robust movement, the watch comes housed in a 40.2mm rose gold case that is water resistant up 30 metres. Its silvery opaline dial features applied gold hour markers with luminescent coating and 18K gold dial plate.

The manually wound mechanical movement Caliber CHR 29‑535 PS Q drives the timepiece offering a power reserve of around 55 hours. The watch is offered on a brown, hand-stitched alligator strap with square scales.

IWC Portugieser Chronograph Rattrapante Edition 'Boutique Canada' Ref. IW371220

Taking inspiration from the design of Portugieser watches from the 1930s, the Portugieser Chronograph Rattrapante Edition 'Boutique Canada' Ref. IW371220 offers  a contemporary look and a robust movement. It features a double chronograph complication for simultaneously measuring two short periods of time.

IWC launched this Portugieser to commemorate  the 150th anniversary of the Canadian Federation in 2017. Limited to 150 pieces, the watch comes housed in a 40.9mm stainless steel case with a silver-plated dial. The totaliser at 12 o’clock and the small hacking seconds at 6 o’clock are black; the hands are rhodium-plated and red. Driven by Calibre 76240, the watch delivers a power reserve of around 44 hours and comes paired with a black alligator leather strap.

Navitimer B03 Chronograph Rattrapante 45  Ref. AB0310211Q1P2

Its rattrapante chronograph and bronze-coloured dial make this Navitimer desirable indeed. Driven by the Caliber Breitling B03 (Manufacture) movement, this watch delivers a power reserve of around 70 hours. The movement finds its home inside a 45mm stainless steel case.

The pushpiece housed in the 3 o’clock crown serves to stop and restart the split-seconds hand as many times as desired during a timing operation so as to measure intermediate (split) times. The Manufacture Caliber Breitling B03 movement was produced by Breitling at its Chronométrie facility in La Chaux-de-Fonds. Its transparent sapphire caseback offers a splendid view of the complex movement.