kz zs3 - Best in ear monitor I've owned. And...they're $15. Insane hi-fi quality. Comparable to my Audio Technica m50x. https://www.amazon.com/KZ-Cancelling-Earphone-Comfort-Headset/dp/B01KUGWNEE

These are pretty awesome, imo: https://www.amazon.com/gp/aw/d/B01KUGWNEE?psc=1&ref=yo_pop_mb_pd_title