Anker has discounted one of its very popular pairs of waterproof headphones, and those are the SoundBuds Surge. These are typically priced at $23.99, but with the promo code JWTDC4PU you can get it for just $16.99. That's good for $7 off of its regular price and definitely makes a worthwhile purchase right now.
The SoundBuds Surge from Anker are a pair of lightweight and waterproof headphones. Now Anker says these are "waterproof" but they are actually just water resistant. That means that these will work great for taking to the gym and using while working out, but don't take these into the shower or the pool, as they likely won't survive a dip in the pool or a shower. These earbuds do also have magnetic tips, so that they can attach to each other and stay together, meaning that you won't need to worry about untangling them when you take them out of your gym bag. The SoundBuds Surge are a very great pair of headphones from Anker, and are definitely a good pair to take to the gym. Especially if you sweat a lot and go through headphones pretty quickly, as these are pretty cheap and won't break the bank to replace them as often as something from Sony, Bose, Beats or Jaybird.
This item is also eligible for Amazon Prime's free shipping. Which includes free two-day shipping, and pretty cheap (usually $3.99) next-day shipping if you need it extra fast. If you are not an Amazon Prime member yet, you can sign up for a free trial of Amazon Prime. You'll get 30 days free (if you're a student, you get 6 months), and then it's $99/year (or $49/year for students). Prime members do get a whole lot more than just free shipping though, so be sure to check out the full benefits.