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  • Castelli - Undersaddle XL Bag -
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  • Castelli - Undersaddle XL Bag -

Castelli Undersaddle XL Bag

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3 Reviews


Bring it all with you.

When you find your saddle bag zipper is straining to shut on nearly every ride it might be time to invest in a bigger bag. Castelli's Undersaddle XL Bag will hold all of your essentials — plus the extras you can't leave home without — but won't add undue bulk to your frame. Made with water and stain-resistant materials and a water-resistant zipper, the bag has Castelli's expected combination of sleekness and style.

The bag's storage features are rounded off with an internal storage pocket and external mini-pump sleeve. It attaches to your frame quickly and securely with a hook-and-loop strap, and even has reflective accents to help keep you visible to motorists, day or night.

  • Item #CST00AI

Tech Specs

1 pump
water resistant zipper
6 x 15 x 6 cm
Recommended Use
Manufacturer Warranty
30 days

Tech Specs

  • Reviews
  • Q & A

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Carry enough impotant things

  • Familiarity: I've used it several times

With this bike I carry a tube,2 tyre lever and bike tool. And still have small free space.
I just use it for 3 rides, each around 100-250 km ride. The shape is perfect for road saddle even with long oval shape f8 seatpost or common seatpost. This saddle bag not make discomfort when pedaling. I haven't test it on wet weather yet. I hope soon rain will fall and try is this bag good in bad weather. Tx

Slick Seat Bag

  • Familiarity: I've put it through the wringer

This is a really nice-looking seat bag, perfect size for a tube, multi-tool, and two CO2 cartridges. Plus it has a special pouch for a mini-pump. It reminds me of the Blackburn bags since it is made of a similar waterproof material. It replaced an Arundel bag, which I liked, but wore out pretty fast. This one has been holding up nicely. One little quip is that the mini-pump will easily come out of the pouch if you don't figure out a way to affix it. The fix I designed for it was two linked zip-ties that catch around either end, so that it won't slip out when I hit the next pot-hole. I had to reduce the rating on this item because after just one rain ride the velcro closures were ruined. I'm back to my tried and trusted Blackburn bag. Not as slick looking, but it withstands more punishment than this fancy bag.