ONstart 310 Sports Stopwatch - Black/Orange



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Made for

regular sportsmen and women or trainers seeking to monitor training sessions with precision
Essential training features: stopwatch, countdown with 50 split times.

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Parameter measurementStopwatch (1/100th sec) with 50 split & lap times
Coaching3 countdown modes depending on the sport: MATCH, COACH and UP&DOWN
AdjustableStride pacer (PACER)
VersatilityTime, date, alarm.
AutonomyAutomatic or manual standby mode for extending battery life
WaterproofWater resistant (1 ATM)
Easy readingLarge digits for perfect visibility during sports.
Easy maintenanceEasily replaceable battery, thanks to the manual opening system.
Warranty2 Years
Technical Information

Stopwatch with 50 split times memory
Up to 99hr 59min 59sec and 50 split and lap times. The stopwatch lets you measure: 1/ the split times = SPLIT: time elapsed from the start, 2/ the lap times = LAP: time elapsed since the last time measurement.
When using the stopwatch, the first 50 split times and lap times are saved in the memory. They can be recalled, whether the stopwatch is working or not. The memory gives access to: fastest lap time, slowest lap time, average lap time based on X recorded values, latest lap time, last lap time but one, etc.
COACH countdown timer
Create your own training session to divide up your exercise programme: - your warm up time (WARM UP) - your acceleration / fast exercises time (RUN) - your recovery / slow exercises time (REST) - the number of RUN accelerations + REST recovery repeats in a series (REPEAT) - the number of RUN+REST series (SERIE) - your rest time in-between 2 series of exercises (BREAK) - your cool down / stretching time (COOL).Up to 99 series and 99 repetitions.
MATCH countdown timer
Countdown with several programmable times (up to 9 blocks and 99 repetitions). Ideal for refereeing a match divided up into several halves.
UP & DOWN countdown timer
Countdown combined with a stopwatch. At the end of the countdown, the stopwatch starts automatically. Ideal in the case of a race that starts with a countdown (e.g. a sailing regatta).
PACER function: stride pacer
The "PACER" is used to set a pace per minute with a beep that sounds at a set frequency. It is combined with a stopwatch. Set the pace you want to follow (from 1 to 240 beeps per minute), and the stopwatch will beep to give you the pace.
Highly legible
Large 3-line display.
Water resistant
This product is water resistant to 1 ATM, i.e. it is resistant to rainfall and humid environments like swimming pools.
A design that has been developed for comfort and precision
The ergonomics of this stopwatch have been designed especially so that the buttons are easily accessible for precision use. The stopwatch's design and its lightweight construction make it comfortable to hold in the hand. Given how important it is to know exactly when you are triggering the stopwatch, you will feel a click when you press a button. Its wide cord is designed so that you can comfortably keep it around your neck.
Extend your battery life
Your stopwatch will no longer remain switched on at all times in your bag. It will automatically switch to standby mode after 24 hours. You can also switch it to standby mode manually.
Choosing the right stopwatch
The range: - OnStart 110: stopwatch with 1 split time, time, date, alarm - On Start 310: stopwatch with 50 split times, MATCH mode, COACH mode, UP & DOWN mode, pacer, water resistant - On Start 710: stopwatch with 300 split times, MATCH mode, COACH mode, UP & DOWN mode, pacer, pace reading, speed reading, water resistant, light - On Start
FunctionCountdown timer, stopwatch

Information / Concept / Technology
Product test
For 20 years, the Geonaute teams have been designing stopwatches specifically for sports use. During their development stage, each model undergoes over 30 distinct tests, and are then tested on the field by our tester team.


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