Rated 5.00 out of 5 based on 3 customer ratings
(3 customer reviews)


5.00 out of 5

The Synaptic is the most stable bottle belt ever created, so stable it goes against the common stereotype that waist packs bounce. Contoured shape for great fit and adjustment points on both sides for one size fits most athletes.

Perfect for road running crowd or for trail racing where aid stations are more plentiful. Race belts are cooler because they cover less surface area of the body, keep weight lower for better balance and are easy and fast to get on and off.

UltraRunning Magazine Top Pick!



Recommended Use:
Racing and training; 1 hour between refueling stops.


• Dual-sided adjustment for good sizing range with single speed hook access for taking waist belt on and off.
• Center front pocket is large enough for cell phone or energy foods with tuck away jacket straps perfect for extra clothing or Z-poles.
• Angled minimalist bottle holster for easy right handed access. Bottle rides close to the body for a comfortable stable ride.
• Synaptic is an MBS™ belt.  Back is compatible and interchangeable with a Lumen 600 front for a hydration and illumination combo.
• Small flat zippered pocket next to holster to secure keys or other essential items.

Fit: Unisex
Size: Universal
Color options: Luminous Blue, UltraRed or Pinnacle Pink (New!)
Hydration (included):  1 x UltraFlask 550
Capacity: 50 c.i.; .85 L

Additional information

Weight 1 lbs
Dimensions 15 x 10 x 5 in

Waist Belt


, ,

Fluid Capacity

550mL UltraFlask bottle

Product Weight (lbs)

Total Volume

34.2 c.i. (.56 L)


3 reviews for Synaptic

  1. Rated 5 out of 5

    I was dreading the day when my old belt wore out and I needed to get a new one. I tried other belts but they would come lose. Thank goodness I found the Synaptic belt. I can use a full 22 oz. water bottle without it bouncing. There is more storage in the front pouch for keys, gels, and supplements. I like this belt more than my previous belt. I use it not only for my long training runs but also for full and half marathons. One water bottle with Hammer Heed is enough to get me through a half. For the full, I start with a full bottle and have a full bottle with Hammer Heed handed to me at miles 9 and 18. This allows me to skip the water stops and drink what I want when I want. This strategy allows me to avoid the sugary electrolyte drinks and help maintain my cadence. I highly recommend this belt.

  2. Rated 5 out of 5

    (verified owner)

    Great for those runs when you only require the basics or don’t want the weight of a larger pack.
    The secure bottle carries sufficient fluid between aid stations for most races. Storage is more than enough
    for minimal needs. The Synaptic is the most stable and comfortable single bottle pack I’ve owned over 42 years
    of racing. Functional, practical, efficient, superbly constructed and great value.

  3. Rated 5 out of 5

    Love my Synaptic belt! I use it for my quick runs where I just want to carry my cell phone, keys, jacket and have 18 oz of water. I also use it on bike rides.

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