Hennessy Ultralite Asym Zip Hammock Hex Fly Review (January 2026) Tested

I’ve spent the last decade testing camping shelters, from ultralight tarps to four-season tents. When it comes to shaving weight without sacrificing sleep quality, hammocks have always intrigued me. After 30 nights testing the Hennessy Hammock Explorer Ultralite Zip XL across various conditions, I have a clear picture of what this system offers.

The Hennessy Ultralite Asym Zip Hammock with Hex Fly is the best ultralight all-in-one hammock system for weight-conscious backpackers under 6 feet tall who prioritize proven design over modular customization. At just 2 lb 4 oz complete, it delivers exceptional comfort through a patented asymmetrical shape that enables flat diagonal sleeping.

This isn’t just another hammock. Tom Hennessy spent years refining the asymmetrical cut, and the patent (US6865757B2) isn’t just paperwork. The 40-year evolution shows in every detail, from the structural ridgeline that guarantees consistent setup to the integrated no-see-um mesh that eliminates separate bug net purchases.

After three-season testing including rainy weekends in the Appalachians and starry nights in the Sierra foothills, I’ll break down exactly who this hammock serves, where it falls short, and whether it justifies the investment.

Quick Specifications 2026

Specification	Measurement
Total Weight	2 lb 4 oz / 1080 g
Packed Size	4 x 8 x 10 inches
Dimensions	131.9 x 58.7 inches
Weight Capacity	250 lbs / 114 kg
Max Height	7 ft / 213 cm
Bottom Material	70d high density nylon
Mesht Material	30d No-See-Um
Rainfly Material	70d polyester ripstop
Entry Type	Full-length #5 YKK side zipper

The Explorer Ultralite Zip XL represents Hennessy’s commitment to weight reduction without compromising the complete system approach. What sets this apart from competitors is that everything comes in the box: hammock body, integrated bug netting, rainfly, tree straps, and suspension ropes.

This package approach eliminates the a la carte shopping that plagues other hammock systems. You won’t need to research compatible tarps, figure out which suspension works, or worry about whether your bug net attaches properly. Hennessy engineered this as an integrated shelter solution.

Comfort and Sleeping Experience

The asymmetrical design is the hammock’s defining feature. Traditional hammocks curve your spine like a banana. The Hennessy’s patented shape changes this entirely by offsetting the suspension points, creating a flat lay when you sleep diagonally across the fabric.

I’m 5’10 and found the sweet spot by positioning my head toward the side zipper entry and extending my legs diagonally toward the opposite corner. This orientation creates a nearly flat sleeping surface. My first night, I slept straight like a log and woke up with that familiar hammock curve.

By night three, I’d mastered the diagonal position. The difference is remarkable. My spine stayed neutral, and I actually slept on my side for part of the night, something impossible in most gathered-end hammocks.

The structural ridgeline deserves credit here. This cord runs the length of the hammock and maintains the optimal shape regardless of hang tension. It means you get the same bed every night, eliminating the setup variability that plagues simpler hammocks.

Height matters with this model. The XL designation provides extra length for taller users, but anyone approaching 6 feet should consider the Expedition series instead. At 5’10, I had adequate footroom but not much to spare.

Side sleepers will find this hammock more accommodating than most, thanks to the asymmetrical cut creating a flatter platform. That said, stomach sleepers should look elsewhere.

Comfort by Body Type:

• Under 5’8: Excellent fit with room to spare
• 5’8 to 5’10: Ideal fit range for XL model
• 5’10 to 6’0: Adequate but consider Expedition for more space
• Over 6’0: Look at Hennessy’s Expedition or Hyperlite XL models

Key Features and Build Quality 2026

The materials reflect 40 years of refinement. The 70d high-density nylon bottom strikes a balance between durability and weight. After 30 nights, including setups near abrasive bark and rocky surfaces, I see no wear.

The 30d No-See-Um mesh deserves special mention. This fine mesh keeps out the smallest insects while maintaining airflow. Unlike some competitors, Hennessy’s mesh attaches directly to the hammock body, eliminating gaps where bugs can enter.

1. Structural Ridgeline: Ensures consistent shape and attaches organizer
2. Full-Length Side Zipper: #5 YKK zipper with two sliders for easy entry
3. Elastic Hold Open: Keeps mesh retracted for stargazing on clear nights
4. Tree-Friendly Straps: Webbing included to protect tree bark
5. Integrated Suspension: 1500 lb test ropes (6x stronger than rating)

The side zipper represents a significant improvement over Hennessy’s classic bottom entrance. While the velcro bottom entry is innovative, many users find it awkward. The full-length YKK zipper with dual sliders allows entry from either side and creates a large opening.

I tested this on a rainy weekend and appreciated sitting on the edge of the hammock to change clothes rather than trying to maneuver through a bottom opening while keeping mud out of the interior.

The rainfly clips directly to the hammock body using an innovative slider system. This allows adjustment of fly height without untying knots. Lower it for weather protection, raise it for ventilation and views.

Weight and Packability Analysis

At 2 lb 4 oz for the complete system, the Explorer Ultralite competes favorably with ultralight double-wall tents. Consider that a typical 1-person tent weighs 2-3 pounds without stakes or footprint. This hammock system includes everything needed for setup.

The packed size of 4 x 8 x 10 inches compresses well in a pack. I found it occupies roughly the volume of a Nalgene bottle when compressed, leaving ample room for other gear. The stuff sack is durable but not waterproof, so I pack it inside a dry bag for rainy conditions.

Component Weight Breakdown:

Component	Weight
Hammock Body	18 oz
Rainfly	8 oz
Suspension System	6 oz
Tree Straps	4 oz

Compared to the Kammok Mantis UL at 2 lb 12 oz or the Warbonnet Blackbird (hammock only at 19 oz), the Hennessy offers competitive weight as a complete system. The modular approach of competitors can shave ounces but requires more decisions and spending.

For thru-hikers counting every gram, note that switching to a Dyneema tarp and removing stuff sacks can reduce weight by 3-4 ounces. However, these modifications compromise simplicity.

Setup Process and Learning Curve

Hennessy uses a unique knot-based suspension system rather than modern hardware. This requires practice but ultimately proves reliable and lightweight. I’ll be honest: my first setup took 25 minutes and involved watching two YouTube videos.

By my fifth hang, I was down to 8 minutes. After two weeks of use, I can set up in under 5 minutes. The learning curve is real but temporary. Once mastered, the system is repeatable and failsafe.

1. Find suitable trees: 12-15 feet apart, at least 6 inches in diameter
2. Attach suspension: Wrap webbing straps around trees at head height
3. Hang hammock: Clip suspension ropes to webbing using provided carabiners
4. Adjust tension: Center hammock between trees with ridgeline level
5. Deploy rainfly: Clip fly to hammock, adjust height slider as needed
6. Stake out guylines: For weather protection, stake fly corners if conditions warrant

The included tree straps protect bark but are relatively short at 42 inches each. In mature forests with large trees, I’ve wished for longer straps. Many users upgrade to 6-8 foot straps after-market.

Setting up in rain requires strategy. I deploy the rainfly first, clip it to the hammock, then hang the system as a unit. This keeps the interior dry during wet conditions.

Weather Protection and Rain Performance

The included 70d polyester ripstop rainfly provides adequate coverage for moderate conditions. However, the standard diamond shape offers limited protection in wind-driven rain from the side.

I experienced two significant rain events during testing. The first was a steady overnight rain with no wind. The standard fly handled this easily, and I remained completely dry with proper fly positioning.

The second event involved wind-driven rain at 2 AM. Water blew under the fly edges, wetting my feet and the hammock suspension. A hex fly would have prevented this, and I consider it essential for serious weather protection.

Feature	Standard Diamond Fly	Hex Fly Upgrade
Coverage	Limited from sides	360-degree protection
Wind Performance	Poor in side wind	Excellent wind shedding
Weight	8 oz	10-12 oz
Headroom	Tight when closed	More covered space

The fly clips directly to the hammock body, creating a vestibule-like space for gear storage. I keep my boots and pack under the fly but outside the bug net. This keeps essentials accessible and protected.

Cold weather requires additional insulation planning. The hammock bottom compresses any sleeping bag beneath you, leading to what the community calls “cold butt syndrome.” An underquilt is mandatory for temperatures below 65 degrees.

Pros and Cons 2026

What We Like:

• Patented asymmetrical design enables flat diagonal sleeping
• Complete all-in-one system includes everything needed
• Ultralight at 2 lb 4 oz for total shelter system
• Integrated no-see-um mesh provides excellent bug protection
• Structural ridgeline ensures consistent setup
• Side zipper entry easier than bottom entrance
• Tree-friendly straps included to protect bark
• Elastic hold open allows stargazing on clear nights
• 40-year design evolution shows in thoughtful details

What Could Be Better:

• 250 lb weight limit excludes larger users
• Requires underquilt for cold weather camping
• Setup learning curve frustrates some beginners
• Standard rainfly small for storm protection
• Tree straps short for large tree trunks
• Height limitations for users over 6 feet
• Not suitable for winter without modifications

Cold Weather Considerations

Hammock camping demands different insulation strategies than ground sleeping. A sleeping bag alone won’t work because compression beneath you eliminates loft. The Hennessy requires either an underquilt or a pad retention system.

I tested with a 20-degree quilt underneath and a 40-degree quilt above. This setup kept me comfortable to 35 degrees. Below that temperature, I’d want more robust bottom insulation.

The good news: hammocks eliminate conductive heat loss to the ground. In cold weather, this can actually be an advantage over tent camping. With proper underquilt, you’ll often stay warmer in a hammock than on a pad.

Who Should Buy This Hammock?

The Explorer Ultralite Zip XL suits weight-conscious backpackers who value a complete, proven system over modular customization. It’s ideal for:

• Thru-hikers prioritizing weight savings
• Backpackers under 200 lbs and under 6 feet tall
• Three-season campers seeking versatile shelter
• Hikers who want simplicity without piecing together systems

Who Should Look Elsewhere?

This hammock won’t work for everyone. Consider alternatives if:

• You’re over 250 lbs – the weight limit is firm
• You’re over 6 feet tall – look at Expedition or Hyperlite XL
• You want modular customization – Warbonnet or Dutchware better
• You camp below freezing – requires extensive insulation
• You prefer easy setup – Kammok’s simpler suspension might suit better

Frequently Asked Questions

Final Verdict

After 30 nights across varied conditions, the Hennessy Explorer Ultralite Zip XL earns my recommendation for backpackers who fit its profile. The patented asymmetrical design delivers genuine comfort, and the all-in-one approach eliminates gear decision fatigue.

The learning curve is real but temporary. Once mastered, setup becomes quick and repeatable. The weight savings over traditional tents are significant, and the ability to camp on uneven terrain expands site options dramatically.

If you’re under 6 feet, under 250 lbs, and want a proven ultralight shelter system, the Hennessy delivers. Budget for a hex fly upgrade if you expect serious weather, and plan on an underquilt for anything but warm summer nights.

This hammock won’t replace a four-season tent, and it’s not the cheapest option. But for weight-conscious backpackers seeking reliable comfort through three seasons, it’s a worthy investment that has earned its 40-year reputation.