These are The Wirecutter's top pick for wired in-ear exercise headphones https://thewirecutter.com/reviews/best-wired-exercise-headph… and it's by far the cheapest price I've ever seen them at.
It looks like the whole exercise range is discounted at present so the iPhone version is also $64.00
https://www.mightyape.co.nz/brands/sennheiser/specials
I bought the older orange version of the full headband model of these sports headphones years ago (the PMX model in your deal link). They were absolutely brilliant for about 9 months and then one ear stopped working. I bought another set and they only lasted about 3 months. So disappointed. Both were bought off Amazon proper (not the marketplace) so I assume they were genuine. All the earpieces were rusted from sweat so I stopped buying them, but I've never found any sport headphones that I like since. Others I've tried since either fall out or sit loose and let too much wind in. I did find some copies at Aldi once for like 3 pounds and bought a few pairs - they sat just as well on the head but didn't sound nearly as good.
My originals were really great and I don't know why more companies don't make the headband sport headphones at reasonable prices. I've seen a few but I'm not prepared to shell out $200 for any pair of headphones now since I found these Sennheisers were full of rust, no matter how good the promises. And they were only about GBP15-20 at the time too - the prices have gone absolutely stupid now. The only difference I can see is the little controller hanging down from the earpiece.
I may try these new models at $65 but I'm a bit put off by that controller - don't want it tugging or flapping when I'm running hard. Still a bit expensive for what they are I think but I've never found anything to replace mine at reasonable prices and I've been keeping an eye out for 7-8 years.
They really did sit tight and had great sound so probably worth it at this price, IF they last.