CROSSO Zipper Tangent Frame Bag

Custom Bikepacking Frame Bag

The Crosso Zipper Tangent Frame Bag is a custom bikepacking frame bag, designed to make the most of the main frame triangle when you need continuous volume with no internal compartments.

Unlike other frame bags organised into multiple compartments, the Tangent is designed for riders who want a single, very spacious storage area, ideal for bulky items that are difficult to fit into bags with internal dividers.

Like the Cosinus, the Tangent is also custom-made for your bike frame, allowing you to use every available centimetre inside the main triangle.

In a bikepacking load system, the frame bag is the element that allows you to carry heavier items while keeping the centre of gravity low and improving bike stability. If you want to explore how to distribute the load correctly across different bags, you can also consult the guide Travel bike bags and bikepacking — guide to choosing, where you will find a section dedicated to load distribution in bikepacking.

A custom frame bag designed for maximum volume

The Zipper Tangent was created with a precise goal: to offer the maximum usable space inside the frame triangle.

Many frame bags use internal dividers to organise the load, but this can limit the ability to carry bulky items.

The Tangent instead uses a single large continuous compartment, which makes it possible to store gear that is difficult to place in other bags.

Typical examples of use:

This type of structure makes the Tangent particularly suitable for long trips and self-supported setups, where load capacity becomes a higher priority than internal compartmentalisation.

The advantage of a custom-made bag

As with the Cosinus, the Tangent is also a tailor-made frame bag.

This means the bag is produced according to the specific measurements of your frame, eliminating the empty spaces typical of universal bags.

The result is:

Another interesting aspect is the price: within the market of custom bikepacking frame bags, the Zipper Tangent stands out for an extremely competitive price range.

At €99, it offers a tailor-made solution at a price often lower than many mid- to high-range standard bags.

Stable mounting system with adjustable Velcro straps

The Zipper Tangent uses a mounting system with adjustable Velcro straps that can be positioned along the edge of the bag.

This system makes it easy to adapt the strap position to the geometry of the frame.

The edge of the bag features a continuous webbing loop system (daisy chain) that allows the Velcro straps to be positioned in the most convenient points, avoiding:

The straps are internally lined with anti-slip material, which improves bag stability and distributes the load better on the frame.

This system also has another advantage: the straps absorb part of the vibrations from the ground, reducing stress on the bag structure.

Materials: durable, waterproof Cordura® TPU

The Tangent is made from Cordura® TPU, a material highly appreciated in bikepacking for its high abrasion resistance.

Main features:

The closure uses a splash-proof zip, designed to reduce water ingress during light or moderate rain.

The bag is made with a stitched construction rather than welded. The fabric is waterproof, but the seams are not sealed. This means it protects well against moisture and moderate rain, but it is not designed for immersion or very intense and prolonged rain.

For water-sensitive items, it is always advisable to use an internal dry bag.

Pockets and quick access

Even with one large single compartment, the Tangent offers some useful features for organisation.

Inner pocket

Positioned under the main zip, ideal for:

External mesh pocket

Located on the side opposite the drivetrain, it allows you to keep small items within easy reach while riding:

How ordering the custom version works

Ordering the Zipper Tangent is simple.

1️⃣ Place the order

Complete your purchase normally and indicate your preferred colour in the order notes:

2️⃣ Receive the measurement guide

After ordering, you will receive an email with detailed instructions on how to take the measurements of the frame triangle.

The guide will take you step by step through collecting the required dimensions.

3️⃣ Custom production

The bag will be produced specifically for your frame with a dimensional tolerance of ±3%.

As this is a customised product, returns are not possible.

Tip for frame protection

Even though the mounting straps are lined with anti-slip material, during long trips vibrations and dust can dull the paint in the contact points.

For this reason, it is advisable to apply frame protection tape in the points where the bag comes into contact with the bike.

Integration into a bikepacking setup

Within a complete bikepacking setup, the Zipper Tangent works together with other bags to distribute the load in a balanced way.

Typical configuration:

This configuration makes it possible to keep the weight close to the centre of the bike, improving stability and control on road and off-road trips.

Technical specifications

FAQ