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OnStart 310, Stopwatch
Essential training functions: stopwatch, countdown, and 50 split times.
Free shipping over $49
Final Sale: No returns or exchanges
See our return rules
Free pickup
San Francisco, 735 Market St. Options
Select an available color and size to see options.
Product Features

Measurement settings
Stopwatch (1/100 sec) with 50 split and lap times.
Coaching
3 countdown modes depending on your sport: Match, Coach, and Up & Down
Adjustable
Pace tracker (Pacer)
Versatility
Time, date, and alarm.
Battery life
Automatic or manual stand-by mode for optimizing battery life
Waterproof
Rainproof (1 ATM)
Easy to read
Large digits for perfect legibility when you play sports.
Easy to maintain
Manual opening makes it easy to replace the battery.
Questions & Answers
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Product Customer Reviews

I was expecting a bit more reliability for the price. As a time keeper at swimming galas, a reliable stop watch is essential when timing 100+ races, but this let met down too many times.
I don't know much about chronos nor what's out there but this one is very responsive and very easy to use.
Good product
Excellent
Yes, It is a high accuracy & precision product, which is complied our ISO testing parameter as we are using the above product to carry out material testing at Quality Control Testing Laboratory, NHPC, Liaison Office, Siliguri.
This product is not comfortable and handy
Product was better then I expected. At this price point just go for it.
Good
I have returned the same and taken my money back. Ideally I Shud be asking decathlon to indemnify me as this product was bought and replaced twice yet finally I had to take my money back. It was not in working çondition. Time waste, hapazard parking omg it was a pain
good choise
Dear Kokozan, thank you for your time in leaving us with a 5-Star rating on our product. We are glad that we managed to delight you with the standards of our product. We really appreciate your loyalty with Decathlon. Please let us know if there is anything else we can improve on in the future. Thank you once again for your time and we hope to serve you again soon! :)
Azreena
Friendly interface and easy to use
Hi He,
Thank you for taking the time to review our products. We are pleased to hear that this item meets your expectations!
We look forward to more of your reviews and sharing! Plus, the new Decathlon app has been launched and you can now purchase all your favourite sports goods with just a few clicks on your smartphone! Yes, it's now available both in the App store and Google Play Store! Download now and happy shopping!
Thank you for your support and stay safe! :)
Sport on safely!
Amalina
CSM Digital Leader
ใช้ดีแต่เสียงดังมากค่ะ มีวิธีปิดมั้ยคะ
สวัสดีครับคุณM
ขอบคุณการรีวิวสินค้าในกลุ่มวิ่งและเดินออกกำลัง
KALENJI นาฬิกาจับเวลารุ่น ONstart 310 ไม่สามารถปิดเสียงได้ครับ
เพื่อให้ทุกคนได้รับประโยชน์และความสุขจากการเล่นกีฬา อย่างยั่งยืน
Sarawoot Promsriroj (JACK)
Trekking bikes & Workshop and Triathlon Enthusiasm
Decathlon Rangsit
Tell 020631990
Line ID: Jackphichit
ถูกดีและทนครับครับ
ขอขอบคุณประสบการณ์ในการใช้นาฬิกาจับเวลารุ่น ONstart 310
ขอให้สนุกกับการออกกำลังกายมีพลานามัยที่แข็งแรงครับผม
Sarawoot Promsriroj (JACK)
Road Running &Triathlon Leader Decathlon Rangsit
Tell +66848336355
Line ID: Jackphichit
Facebook: Sarawoot Promsriroj
อยากให้สามารถ lap time ได้ถึง 100
ขอขอบคุณประสบการณ์ในการใช้นาฬิกาจับเวลารุ่น ONstart 310
ขอให้สนุกกับกีฬาและมีสุขภาพดีครับผม
Sarawoot Promsriroj (JACK)
Road Running &Triathlon Leader Decathlon Rangsit
Tell +66848336355
Line ID: Jackphichit
Facebook: Sarawoot Promsriroj
да
Здравейте,
Благодарим Ви за отделеното време и оценката, която сте дали за нашия продукт. Качественото обслужване, доволните клиенти и предоставянето на възможността всички да спортуват е наша главна цел.
Спортни поздрави,
Екипът на Декатлон България!
Additional Product Information
Composition
Structure
- 80% Acrylonitrile butadiene styrene
- 20% Acrylic
Inner tent
- 80% Pcba
- 20% Battery - Lilo
Stopwatch with up to 50 saved lap times
Up to 99 hrs 59 mins 59 sec and 50 split times (split and lap). The stopwatch measures the following: 1/ split times = Split: the time elapsed since the start, 2/ lap times = Lap: the time elapsed since the last lap time measurement.
Memory
When using the stopwatch, the first 50 split times and lap times are memorized. They can be recalled, whether the stopwatch is running or not. You can view the following in the memory: the fastest lap time, slowest lap time, average lap time out of the X saved times, last lap time, penultimate lap time, etc.
Coach countdown
Create your training session to manage your efforts: - your warm-up time (Warm Up) - your acceleration / fast exercises time (Run) - your recovery / slow exercises time (Rest) - the number of run and rest in a series (Repeat) - the number of run + rest exercise series (Series) - your time between 2 series of exercises run+rest (Break) - your end-of-session / stretching time (Cool). Up to 99 series and 99 repetitions.
Match countdown
Countdown with several programmable times (up to 9 blocks and 99 repetitions). Perfect for refereeing a match with several periods of play.
Up and down countdown
Countdown associated with a stopwatch. At the end of the countdown, the stopwatch starts automatically. Perfect when starting a race with a countdown (e.g. at a sailing regatta).
Pacer function: stride pace
The Pacer means you can set a pace per minute with beeps at set intervals. It is combined with a stopwatch. Set the required rate (between 1 and 240 beeps minute), and the stopwatch will beep at this rate to give you the pace.
Perfect visibility
Big screen with a 3-row display.
Rainproof
This product is waterproof at 1 ATM, i.e. resistant to rain and use in a damp atmosphere such as a pool.
Specially designed for comfort and precision
The ergonomics of this stopwatch have been carefully designed so that the buttons are accessible and can be used with precision. The design of the stopwatch and its lightweight construction mean you can hold it comfortably in your hand. Because it is crucial to know precisely whether you have activated the stopwatch, you will hear a click when you press a button. The wide strap will let you keep it comfortably around your neck.
Save your battery
Your stopwatch will not stay on forever at the bottom of your bag. It automatically goes to stand-by mode after 24 hours. You can also switch to stand-by mode manually.
How to choose the right stopwatch
The range: - OnStart 110: stopwatch with 1 split time, time, date, alarm - OnStart 310: stopwatch with 50 split times, Match mode, Coach mode, Up & Down mode, speed pacer; rain-resistant - OnStart 710: stopwatch with 300 split times, Match mode, Coach mode, Up & Down mode, speed pacer, pace tracker, speed tracker, rain-resistant, light - OnStart:
Origin
Imported
Product testing
Decathlon teams have been designing watches specifically for sports use for 20 years. During development, each model undergoes more than 30 different tests in the laboratory, as well as some tests in the field conducted by our teams of testers.
Guarantee
Essential parts (battery) available: 2 years
Superior quality. Unbeatable prices.
For 40 years, Decathlon has delivered the best value in the retail sports industry by offering high-quality, sustainable and cost-effective products.
Decathlon makes the difference
-
Research and development
delivers high-quality cost-effective products
-
State-of-the-art production processes
minimize manufacturing costs
-
Optimized supply chain
reduces retail prices
-
Minimal retail footprint
lowers overhead and indirect costs

OnStart 310, Stopwatch
Your location: City, ST
Please enter a valid city with state or zipcode. Example: San Francisco, CA or 94101
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Heavy products return policy
If you return a product you will receive a refund for the purchase price plus any applicable sales taxes, less any non-refundable charges.
Decathlon will cover all shipping costs associated with your return except for items excluded from our return policy such as bikes, basketball hoops, snowboards, surfboards, tents, and other larger / heavier items.
Return costs for heavy products:
Weight Thresholds | Shipping within California | Shipping outside of California |
---|---|---|
> 9 lbs | $20.00 | $25.00 |
> 30 lbs | $50.00 | $65.00 |
> 100 lbs | $100.00 | $125.00 |
> 200 lbs | $200.00 | $230.00 |
If you return a product at any of our store locations, we will gladly help you find the best alternative product or refund you on the spot.
