Rated 5.00 out of 5 based on 1 customer rating
(1 customer review)


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 N/A
Dimensions N/A

Waist Belt


, ,

Fluid Capacity

550mL UltraFlask bottle

Product Weight (lbs)

Total Volume

34.2 c.i. (.56 L)


1 review for Synaptic

  1. Rated 5 out of 5


    I take this belt with me everywhere. Whether it’s a short walk or longer run. It holds just the right amount of water. I love that the bottle is so soft that I can suck out the air half way through and squish it down to reduce sloshing. I put my keys in the back zippered compartment. In the front, I like to carry my cards/ID (there’s two inner pockets for this). I always listen to my music and the front pocket fits my phone perfectly. I usually start my run out with a light jacket and then take it off and loop it through the shock cords on the front of the pack. Sometimes my jacket is heavier and I still don’t feel a bounce when it’s attached. It’s awesome!

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