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Polar T31 Coded Transmitter

by Polar
4.4 out of 5 stars  See all reviews (45 customer reviews)
RRP: 33.39
Price: 25.69 & FREE Delivery in the UK. Details
You Save: 7.70 (23%)
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In stock.
Dispatched from and sold by Amazon. Gift-wrap available.
Want it tomorrow, 24 July? Choose Express delivery at checkout. Details
  • Coded transmitter unit
  • Works with current models except CS600 and RS800 but only eliminates interference (cross-talk) when used with a coded wrist or head unit
  • Set includes sealed coded transmitter and elastic strap(M)
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Frequently Bought Together

Polar T31 Coded Transmitter + Polar Chest Strap - Spare, S
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Product details

  • Product Dimensions: 0.1 x 0.1 x 0.1 cm ; 9 g
  • Boxed-product Weight: 91 g
  • Delivery Destinations: Visit the Delivery Destinations Help page to see where this item can be delivered.
    Find out more about our Delivery Rates and Returns Policy
  • Batteries 1 Nonstandard Battery batteries required. (included)
  • Item model number: 920135
  • Date first available at Amazon.co.uk: 19 Aug 2008
  • Average Customer Review: 4.4 out of 5 stars  See all reviews (45 customer reviews)
  • Amazon Bestsellers Rank: 4,131 in Sports & Outdoors (See Top 100 in Sports & Outdoors)
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Product Description

  • Power Source: Battery
  • Junction: coded

Customer Questions & Answers

Customer Reviews

Most Helpful Customer Reviews
14 of 14 people found the following review helpful
5.0 out of 5 stars easy replacement strap 16 Nov 2009
Verified Purchase
I got this as my T31 strap stopped working with my Polar HRM after about 2 years. I thought I would have to sync or somehow configure the watch to accept the new strap but it started working as soon as I put it on. Neat!

For anyone having problems just remember to wet the hatched areas that go against your skin. I give them a quick lick which does the trick.
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50 of 52 people found the following review helpful
5.0 out of 5 stars All you need for gym-based heart monitoring 3 Aug 2009
This review was amended in January 2013 order to make clear the distinction between the Polar T31 transmitter and the separately available Polar wristband displays.

The T31 is the standard Polar chest band heart rate transmitter. It is also available in a package with Polar wrist band heart rate displays such as the Polar F4, F6, F7 etc.

If you work out in a gym equipped with modern treadmills, cross trainers, steppers, cycle exercisers etc you will find that the machines are all capable of picking up and displaying the heart-rate signals transmitted by the T31. So if you only work out in the gym using modern exercise machines (e.g. Technogym) just buy the T31 at less than half the price of the full transmitter and monitor package. If you later decide to use it for running, cycling or swimming, just add a Polar wrist band monitor.

The T31 is good value for money, in my opinion. Just ensure that the two conductive strips (look like carbon fibre) on the inner face are slightly damp before starting: once you get into the calorie burning zone your perspiration will keep them that way!
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5 of 5 people found the following review helpful
5.0 out of 5 stars Works fine 6 May 2010
Verified Purchase
Pretty boring item to review but worked absolutely fine with all the cardio machines (Life Fitness) at my gym.
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3 of 3 people found the following review helpful
Verified Purchase
Is an excellent transmitter, the gym near where i live have all Technogym equipment Excite+ range and the sensor works in all of them, is great!!
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1 of 1 people found the following review helpful
5.0 out of 5 stars works for swimming 19 Mar 2013
Most heart rate monitors seem to be water resistant, which means they dont drown when you go swimming, but it says nothing about whether they work while under water.
I like swimming and this pickup works under water. I wanted a heart rate monitor to help gague how hard I was working. I get sensible values for heart rate while in the water (unlike some others which only work when you take them out of the water). I beleive this is down to the frequency of the radio transmitter, and its relation to water, with high frequency transmitters being blocked by the water.
I have also seen comments suggesting that the heart signal gets shunted by chlorinated water, all I can say is it has never afected my use of this one.
I did read a review that said these can be disloged if you swim very fast. I can confirm that, but I cant swim that fast for more than half a length, and I suspect that tightening the strap might cover that off too.
I think this works with gym equipment as well, as when I was wearing it, the machines in the gym seemed to pick up my heart rate without me holding on.
The one down side that I can see after buying it is that the battery is NOT user replaceable. The assembly is glued together and sealed. these seem to have to be returned to polar for new batteries. (probably just a replacement unit). I havent run mine out of battery yet (four months) so I have not tried getting a replacement yet.
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1 of 1 people found the following review helpful
5.0 out of 5 stars Heart rate monitor transmitter 11 Mar 2012
By BrianC
I've used these transmitters for a number of years and they either work or they don't. This one works fine, it worked straight out of the packaging. Delivery was fine, arrived as promised though the box it came in was enormous, my wife thought I'd spent a fortune on some gadget or other.
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5.0 out of 5 stars Faultless performance 30 Jun 2014
By Tim
Verified Purchase
My old Polar HRM was probably around ten years old and, while it still functioned electronically, the plastic was weak and treating apart to the point of breaking. The replacement works perfectly and should be good for several years to come. I use it with a Polar Vantage NV watch, which itself is over fifteen years old and only needs DIY battery replacement (50p each time) less than once per annum.
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5.0 out of 5 stars Polar T31 Replacement Transmitter 16 Jun 2014
Verified Purchase
Unit built to same standard as the original one delivered with heart rate monitor. Works fine and connects every time.
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Most Recent Customer Reviews
1.0 out of 5 stars One Star
It works fine but you cannot replace the battery. Mine is now useless.
Published 14 hours ago by D ONEILL
5.0 out of 5 stars works great. comfortable to wear
works great. comfortable to wear. bought it mainly to wear when in the pool but more comfortable than the one that came eith the watch so use it all the time now. Read more
Published 2 days ago by O
5.0 out of 5 stars Mint
Mint works like a charm, never have to pre program anything again just pop the strap on and away I go on the exercise machines.
Published 1 month ago by Richy
5.0 out of 5 stars Does what it says
Works just like the old one, its comfortable and easy to clean. I use it with a very old X Trainer watch
Published 2 months ago by Mr. James Clarke
5.0 out of 5 stars Replacement chest strap.
This is a replacement for a Polar HR monitor and chest strap. It appears more comfortable than the one it replaced but as the batteries cannot be changed I suspect it is the only... Read more
Published 2 months ago by Richard Findlay
5.0 out of 5 stars No setting up
So easy to use but expensive as cannot change battery so had to order this as replacement for previous transmitter that was in perfect order except for dead battery but it had... Read more
Published 2 months ago by sauntering
5.0 out of 5 stars Fully functional replacement
After getting intermittent performance on my Polar fitness watch I considered replacing it but the latest version looks cheap and nasty so thought I would try a new belt first. Read more
Published 3 months ago by D. J. Jackson
4.0 out of 5 stars replacement chest strap
I have used this monitor for a few years, this is a replacement. As a piece of kit I have always been impressed , it is accurate and talks to the gym equipment I use. Read more
Published 3 months ago by pepsimax
5.0 out of 5 stars I love this HRM, its so easy to use and it is easy to clean and store...
I would recommend this product to anyone - so easy to get going no fuss and the attachment strap is top banana :-)
Published 4 months ago by Happy Days
5.0 out of 5 stars Works but was sent T31 instead of T31c
I received the polar T31 transmitter instead of the polar T31c transmitter so be careful with what you get, cause it might be the wrong one!
Published 5 months ago by becccci
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