With a variety of colors and sizes the Guppy Seat Bag is a great option for storing essentials. The Guppy comes in three sizes - small, medium and large. The small can hold 25 cubic inches/0.4 L of storage while the medium can hold 40 cubic inches/0.6 L and the large 100 cubic inches/1.6 L. The Guppy is also very lightweight. The small, medium and large weigh in at 4 oz/113 g, 4.5 oz/128 g and 5 oz/142 g respectively. This is great for me as I hate adding more weight than necessary, but still feel a seat bag is essential. The Guppy has color options of orange, pea green, royal blue, sky blue, yellow, black, red. With different sizes and colors users can pick the Guppy that suits their needs and style. 

The Guppy attaches under the saddle quickly and easily with two Velcro straps (one on each side) in the midpoint of the Guppy which loop around the underside of the bike seat. A rubber strap at the front loops around the seat post for another attachment point. The Guppy uses rubber instead of Velcro for the front loop which means biking shorts are not damaged thus prolonging their lifespan. I love this as other seat bags with a front Velcro attachment will eat my bike shorts which cost significantly more than most saddle bags.

The Guppy has a zippered opening with an inverted ‘Y’ shaped pull-tab to help open up the mouth of the bike seat bag. The Guppy has a key ring that is attached to the Guppy with a thin webbing strap. This strap connects to the lower inside lip of the Guppy. With the key ring, I can quickly get the key to the car or front door without having to empty the Guppy. The large opening on the Guppy is a part of the saddle bag’s design. I don’t have any issues accessing items in the Guppy. The opening is large enough that I can fit all of my fingers except my thumb inside.

I received the medium Guppy in a sky blue to review. I can squeeze a spare road tube, patch kit, key, a tire lever and a credit card in the Guppy. For mountain biking I feel the medium is too small and I would need the large instead but again you need to pick the right size for your style for riding. The large mouth makes packing or accessing gear stored in the Guppy a breeze. 

The Guppy is a great, lightweight option for storing essential gear under the seat. The wide opening makes it easy to get to gear stored within the Guppy. The Guppy attaches to the seat easily and the front attachment is not Velcro so it won’t destroy cycling shorts. The medium is a good size for a road bike but a little too small for a mountain bike. One should take into account what type of riding when deciding on which size to purchase. Overall I believe the Guppy is a great addition to anyone’s bike.