The Arundel Uno takes a minimalist approach to flat repair storage. This bag carries one road tube, a couple of tire levers, a CO2 cartridge, and an inflator without adding bulk or weight under your saddle. If you prefer traveling light and keeping your jersey pockets free, the Uno holds just enough to get you rolling again after a flat. The 25 cubic inches of capacity fits the essentials without creating a swinging mass that rattles or rubs against your legs. Some riders pack tighter by compression-wrapping their tube, which creates a bit more room for a small multi-tool or emergency cash.

Unlike Arundel's other bags that hang vertically, the Uno mounts horizontally beneath the saddle rails using a single hook-and-loop strap. The strap is sewn double-thick so it maintains tension and stays cinched tight once you secure it. A leather patch sits between the bag and your seatpost clamp, protecting the nylon fabric from abrasion and punctures where it contacts the hardware. This detail extends the life of the bag considerably, especially if you frequently remove and reinstall it. The strap loops through the saddle rails and wraps around the bag, creating a secure connection point without requiring a second strap around your seatpost that can wear through frame finishes.

The bag measures roughly 4 inches by 3 inches by 2 inches and tucks up close to the saddle when properly tightened. The horizontal orientation keeps the bag's profile low and out of the way while you pedal. The zipper runs across the length of the bag and opens wide enough to access your gear without fighting the opening. At 63 grams, the weight penalty is negligible. If you need room for a second tube or larger tools, Arundel's Dual bag offers more capacity with similar construction quality. The Uno works well for riders who pack only what they absolutely need for roadside repairs and want to avoid carrying extra weight or bulk on training rides and races.