Ultra-Sil Day Pack

It stuffs down to a size smaller than a baseball. Its manufacturer, Sea to Summit Inc. of Perth, Australia, suggests using it as a keychain. But unpack the Ultra-Sil Day Pack and its crinkly “siliconized” Cordura nylon quickly takes shape, a backpack materializing from a tiny ball right in front of your eyes.

As outdoors products go, the Ultra-Sil Day Pack is certainly strange. It is far from technical gear. The backpack, a basic sack equipped with shoulder straps, carries its stowed items with scant support. Lumps protrude from the thin fabric where a shoe or a water bottle might be stuffed inside. Objects dig into your back.

But what this $28 backpack lacks in performance it gains in improbable convenience. The Ultra-Sil Day Pack weighs just 2.4 ounces. It fits in any pocket. Unzipped and open, there’s about 20 liters of space inside — enough area to stow a day’s worth of supplies while travelling.

The company (www.seatosummit.com) markets the Ultra-Sil as a “super strong pack that clips on your keychain to shoulder groceries or scramble a summit.” You could easily put it in your pants pocket and bike to the store, load in groceries, and wear it home.

Other uses for the water-resistant pack include carrying wet gear after a day outside. Stash your sweaty clothes in the pack after a triathlon or other event. The company mentions using the pack for “messy stuff” like dirty laundry after a weekend of camping.

I might think twice before scrambling to the aforementioned summit with this pack. But in a pinch, if the Ultra-Sil is what’s available, this siliconized sack with shoulder straps can do the job. It can carry water, food, some gear, and extra clothing layers for a hike.

Indeed, Sea to Summit has tested the pack for maximum weight. The fabric used for the pack, which has bar-tack reinforced stitching at stress points, resists loads of up to 350 pounds, the company cites. But a company representative said this much weight far exceeds suggested use amounts. The spokesperson expanded, “It’s likely they’ll cut their arms off before they reach their destination.”

—Stephen Regenold writes about outdoors gear at www.gearjunkie.com.