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Backpacks for Skiing

The Duel: Dakine Hot Laps vs. Osprey Seral

Two mountain bike waist hydration packs reviewed and compared.

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Some mountain bikers are confident enough in their bikes and their own stamina that they readily head out on a ride with only the shirt on their back and a single water bottle crammed in their bike’s bottle cage. I am not that mountain biker. Whether I’m headed out for a quick 10-mile lap on a local trail, or a 20-plus mile sufferfest, I carry a spare tube, hand pump, tire lever, multi-tool, energy snacks, and at least 1 liter of water.

I normally stuff all these items in an over-the-shoulder hydration pack and just deal with aching shoulders and a seriously sweaty back after each mountain bike ride. Only recently did I realize I had another option: a waist pack with built-in hydration system. Two new options on the market this summer: the Dakine Hot Laps 5L Bike Waist Bag and Osprey Seral lumbar pack.

Dakine Hot Laps 5L Bike Waist Bag

Dakine Hot Laps 5L Bike Waist Bag
Photo courtesy of Dakine

New from the trusted pack and mountain bike brand Dakine, the Hot Laps 5L Bike Waist Bag is a great option for riders looking for a lumbar pack that will hold all the essentials. Made from bluesign approved nylon ripstop and polyester, the Hot Laps bag is durable and functional and designed with the rider’s comfort in mind.

The waist bag features two main zippered compartments, with the front cargo pocket designed to organize your tools, snacks, phone, and leave room for a light shell, while the back compartment firmly stashes and secures the included 2 liter, lumbar-shaped Hydrapack reservoir. A magnetic buckle located on the side of the waist belt helps lock the hydration pack hose in place on-the-go and helps auto-locate the hose when you’ve dropped it after taking a swig. Last but certainly not least (this is, after all, the reason to ditch the traditional backpack): A breathable AirFlow back panel allows air to reach the lower back and prevent pack sweat.


  • The magnetic buckle holds the hydration pack hose in place even while riding over rough and uneven terrain.
  • The designated hole for the water hose in the hydration pack compartment helps guides the hose to stay snugly against the waist belt rather than flop around during your ride.
  • The contoured shape of the bag and easily adjustable waist straps mean the Hot Laps fits comfortably and stays put during the ride.


  • Because the bag is compact and contoured, and the hydration pack carries more volume, it can be difficult to fit some of the essentials (like hand pump, extra layer) in the front zipper compartment.

Dakine Hot Laps 5L Specifications

  • $53-$75
  • 2L / 70oz Hydrapak® lumbar reservoir
  • Phaser bite valve
  • Magnetic buckle auto-locates hydration hose
  • Breathable Air Flow back panel
  • Internal organizer pockets
  • External attachment straps
  • Side compression

Osprey Seral

Osprey Seral Lumbar Pack
Photo courtesy of Osprey

Slightly larger than the Dakine Hot Laps waist bag but with a lower-volume hydration pack, the new Osprey Seral lumbar pack is a great option for longer rides where you may need to schlep more supplies with you.

Like the Dakine Hot Laps bag, the Seral features two main zippered compartments—one for the included 1.5L water reservoir, and a roomy front pocket big enough to hold your phone, hand tools, extra layer, tube, and hand pump. Energy bars can go in the Seral’s two zippered hipbelt pockets for easy access while riding. Another cool feature of the Seral is the Osprey proprietary Hydraulics® reservoir by Hydrapack, which compresses and distributes water evenly across the pack for stable carrying. 

Like the Dakine Hot Laps, the Seral features a magnetic hipbelt bite valve attachment for easy access to the hydration hose while riding and no-fuss storage between use. Osprey’s AirScape back panel helps sweat escape and promotes airflow to the low back during the ride and provides extra cushioning to ward off friction and hotspots.


  • Even when the hydration bladder is full, the Seral fits everything you need and more thanks to additional hipbelt pockets for energy bars and roomy zipper compartments. 
  • The Osprey Hydraulics reservoir distributes water more evenly across the pack and along the sides of the hip for less sloshing/bouncing around.


  • Even with compression straps along the hipbelt to cinch the load closer to the body, the Seral does not fit as comfortably as the Dakine Hot Laps.
  • The magnetic hipbelt bite valve attachment to hold the hydration hose in place is not as strong as the one on the Dakine Hot Laps bag, and the Seral’s hose regularly comes unclipped when riding over rough and uneven terrain.

Osprey Seral Specifications

  • $85
  • 1.5L Osprey Hydraulics® 1.5L reservoir by Hydrapack
  • Magnetic hipbelt bite valve attachment
  • Dual zippered hipbelt pockets
  • AirScape back panel with contouring lumbar wrap for maximum stability
  • Zippered main compartment with internal tool organization

The Verdict: Dakine Hot Laps

If you’re looking to ditch traditional over-the-shoulder mountain biking packs in favor of a waist bag that will let your back breath, reduce stress on your shoulders, and make you work on becoming a more minimalist packer, both the Dakine Hot Laps 5L waist bag and Osprey Seral lumbar pack are great options. While the Osprey Seral is a great pack for riders who carry more gear on their rides, the Dakine Hot Laps is a snugger-fitting pack that moves with you over terrain rather than against you. But the biggest benefit to the Dakine Hot Laps bag is the stronger magnetic valve clip which holds the hydration hose in place over roots, rocks, and drops.