My phone is about as integrated into my life as my left temporal lobe. I’m not going running without it.

That’s why the H2O Audio Amphibx Fit Armband ($60) is a boon for technophile exercise-junkies like me. Sure, it’s ugly, and its large size dwarfs my skinny arms. But with my phone tucked inside, I can go running in rain, sleet, hail or any other ridiculous elements without fear of water damage. I can even go swimming with my Precious — something even Sméagol would envy.

Coupled with a pair of H2O Audio’s Surge 2G headphones ($50), which are also waterproof, I can listen to music anywhere I choose to run, splash or ride.

The Amphibx armband is essentially a sealed, clear plastic pouch attached to a beefy fabric-fastener strap. On the back there’s a double-latching hatch with a gasket. Pop your phone inside, clip the latches down and the gasket seals all water out. It also seals air inside, so your phone gets to ride along with a bubble of air, which helps it float should it become detached.

You can still work your phone’s controls and use its touchscreen through the pouch, although it’s a bit more awkward than before.

To use headphones, you connect the armband’s internal plug to your device before sealing it inside, then close up the pouch. Afterward, you can plug your earbuds or headphones (regular or waterproof) into the armband’s external headphone port, making an electrical connection without compromising the waterproofing.

I tested the Amphibx armband and Surge 2G headphones in a variety of conditions, from jogging on a hot and sweaty California afternoon to running through chilly, blowing Seattle rain. I took it in the shower and on 1-mile pool lap swims. I used it with an iPhone 4 as well as a Motorola Defy. Neither phone ever saw a drop of water, except for the random few drops that fell on them as I was reopening the case after a workout.

The case is big enough to hold the well-endowed HTC Evo, although it’s a bit of a squeeze once you connect the internal headphone plug. You can also can fit a credit card or a $20 bill inside along with the phone.

The Surge 2G headphones performed just fine while running, with decent sound and a rugged design that made them relatively easy to deal with while exercising. However, I was not able to get the headphones to stay in while swimming. It might be that my ears are unusually-shaped, but they kept floating out in the water, even when I’d jammed them well inside my outer ear. Switching to different tips (several sizes are included) didn’t help much.

Still, for running and other sport activities in wet environments short of total immersion, the H2O Audio combination works well. Whether you just want to take music with you, can’t stand being out of touch or are using your phone to track your workouts, these two are a pricey but practical pair of accessories.

WIRED Waterproof to 12 feet: Good enough for surfing! Wide fabric-fastener strap keeps armband on even when severely buffeted. Easy to adjust.

TIRED Plastic sticks to touchscreens, making removal slow. Harder to work touchscreen controls through the plastic. Plastic adds glare in bright sunlight. Size will make your arms look even skinnier, you nerd.

Photos by Jon Snyder/Wired.com