Which is better for swimming?

The Nank Runner Diver2 Pro. Its IP69 rating covers swimming and diving, and the 32GB MP3 mode lets you listen without a phone in the water. The Shokz OpenRun Pro is IP55 and not meant for submersion.

The Shokz OpenRun Pro. Its 9th-generation bone conduction with TurboPitch bass enhancers and two EQ modes gives fuller, cleaner audio, and reviewers rate its calls highly. The Nank trades some sound polish for noise-canceling and storage.

Both are rated at 10 hours. The Nank charges faster from empty in short bursts, giving about 120 minutes from a 10-minute charge, while the Shokz gives about 1.5 hours from 5 minutes.

Is the Nank worth stepping up to over the Shokz?

Only if you swim or want phone-free music. For running, cycling and calls, the Shokz's fit, sound and mic quality make it the better daily headset.

Can I take calls on both?

Yes, both have microphones. The Shokz has dual noise-canceling mics tuned for voice and reviewers praise its call clarity; the Nank's noise-canceling targets wind and ambient noise instead.

Do either work with a swim cap or helmet?

The Nank's hook rotates up to 35 degrees and is designed to fit under caps, goggles and helmets. The Shokz titanium frame sits over the ear and works under a helmet but is not built for swim caps.

Shokz OpenRun Pro vs Nank Runner Diver2 Pro

Pick the Shokz OpenRun Pro for running, cycling and everyday calls: it has the more refined bone-conduction sound, a secure titanium frame and strong voice-call quality. Pick the Nank Runner Diver2 Pro if you swim or train in heavy water and want a built-in MP3 player so you can leave your phone behind. The Shokz wins on audio polish and fit; the Nank wins on waterproofing, onboard storage and newer Bluetooth.

Choose the Shokz OpenRun Pro if you want the better-sounding, better-fitting open-ear headset for running, riding and phone calls.
Choose the Nank Runner Diver2 Pro if you swim, dive or want 32GB of onboard music so you can train without a phone.

Prices

Shokz OpenRun Pro: $89.99 at eBay (last seen Nov 8)
Nank Runner Diver2 Pro: $89.96 at eBay (last seen Nov 8)
Difference: the Nank Runner Diver2 Pro is $0.03 cheaper than the Shokz OpenRun Pro at the latest prices (Nov 8)