Sennheiser's HD1 in-ear wireless headphones are currently on sale over on Amazon, as part of its Gold Box Deal of the Day. It is priced at just $149, which is $50 off of its regular price. And it also marks the first time that these have been discounted since release.
The HD1's are neck-band style earbuds, which are a pretty popular form of earbuds these days. These are Bluetooth 4.1 headphones, so they will work with those smartphones that have dropped the headphone jack, like the Pixel 2, Essential PH-1 and others. It does also support the AAC codec and apt-X, so that you'll get some crystal clear sound out of the Sennheiser HD1, of course that is to be expected, since Sennheiser is basically known for its audio quality. These are slated to last around 10 hours on a charge, and a depleted HD1 can be recharged in just an hour and a half, allowing you to quickly recharge these before your workout. These are sweat and weather resistant, making them great for the gym.
This is also eligible for Amazon Prime's free shipping. Which includes free two-day shipping, and pretty cheap next-day shipping if you need it here extra fast. If you are not an Amazon Prime member yet, you can sign up for a free trial of Amazon Prime by hitting the link below. You'll get 30 days free (if you're a student, you get 6 months), and then it's $99/year. Prime members do get a whole lot more than just free shipping though, so be sure to check out the full benefits.