I had a previous version of this product, here’s the review I placed when returning them: This is probably a design flaw endemic to all earbuds with a similar design but I bought and returned these. As I started running the left earbud sound kept coming in and out and finally went dead altogether after a half mile. I shut down and restarted and the left earbud stayed active but sound kept dropping in and out, almost like a radio signal dropping in and out as you drive in the mountains. I was on a beach so no mountains. After a few miles I had a suspicion and switched my watch to my right wrist. No issues whatsoever. I switched it back to the left wrist and the drops returned. Apparently the bluetooth receiver is in the right earbud and as your arms move your body gets between the watch on your left wrist and the receiver on your right ear. If you are dense enough your body blocks the signal. I can’t wear the watch on my right wrist for long due to physical issues so these headphones will never work for me.
A while back I bought the HELM Audio True Wireless Earbuds from Woot, and I have the same issue. If I’m sitting at my desk, they work as expected. However, if I walk around the block or exercise at the gym with them, the left earbud cuts in and out constantly. Maybe higher-end earbuds use a higher bluetooth version and don’t have this problem?
I was considering these until…“MicroUSB charging cable”… 
I’ve finally gotten all my devices on USB-C.
I’m not carrying around an old cable for these.