I’ve read that this “should” work and that the polar straps should last longer before failure. I need a new strap for my garmin HRM.
I tried my polar strap and despite the button thingies looking like they’d match up fine, the garmin HR part with the battery has enough plastic surrounding the metal buttons that it doesn’t quite click home.
Anyone “adjusted” the back of the garmin to make it fit? I suspect a scrape here and there with a knife would be sufficient.

I use a Garmin HRM on a Polar strap. It fits perfectly with no modification (previous generation and HRM-RUN both work for me).

+1 to what Flaperon said.

Which Garmin unit are you using, and which Polar strap? I have the HRM-Run and a Polar Wearlink style strap. DC Rainmaker Article

Aside from it being less prone to breaking (which I didn’t experience), the Polar strap is much more reliable with the measurements staying consistent. I experienced the Garmin strap causing a drop of in HR after 20-30 minutes: I know I don’t run at a HR of 75bpm…

Yep
My Garmin is a ~2011 HR transmitter that came with an FR60 watch with Premium soft strap.

The back looks like this:

The Polar strap is from the new M400 watch, so it is an H7 model (are the straps different across different polar straps?). The buttons look just like the image in DC rainmaker article. As the plastic around the metal comes up just to the top of the female part, hence fouls the back of the garmin transmitter.

The “plastic” on a Polar strap is soft (at least it is on mine) and presents no problem to clipping the receiver on.

How much is a compatible HRM unit as my H7 has died on me?

Have done this (with the Garmin ‘premium’ HR module and a Polar strap). As Flaperon says, it should Just Work – the studs don’t line up perfectly but it’s close enough, and no modification should be needed.

totally not answering the OP, but saying it anyway 8)

I’m using a Mio wrist HR monitor to feed data to my garmin. Works great (so far) and I’m finding it far more comfortable than a chest strap. Longevity remains to be seen.

Seems universally accepted that this should work. I’m going to try convincing it a bit harder to fit then.
Thanks all.

Out of interest, is there any combined ant+ and Bluetooth combined chipset hrm that I could use for both my polar watch and garmin unit?

The Mio Link or Fuse wrist heart rate monitors can transmit both Ant+ and Bluetooth Smart. Or for a chest strap, the Wahoo Tickr transmits both.
So they should work with the Garmin and the Polar.

Only echo’ing from earlier comments but the Polar Wearlink+ strap works with the previous [Garmin] generation HRM pod, and the current Run-HRM pod.

I’ve used the Polar strap in preference to the Garmin straps with my 910 for > 18 months, and I’m doing the same now with my F3, and both pods work fine.

There is a tiny bit of a size difference in the spacing ‘twixt pod and strap, so you may notice a very slight tuck/fold in the strap with the pod attached, but we are only talking about a tiny difference – certainly nothing that impacts on use/comfort.

Also – if you want any of the HRV data (for recovery times / VO2max calculations / TE etc) you’ll have to use an ECG-based heart rate strap. Optical monitors can send the data, but only with low accuracy.

Others would say that calculating anything based on HRV is utter bollocks and it doesn’t matter.

Garmin compatible chest strap
Have used this for about 10 rides so can’t vouch for its longevity. But I have bought a spare. Looks to be posted in GB, and arrived pretty quick . Mate bought one too, he rode the south downs way last weekend with it.