Box One Disc Brake Adaptor

The BOX One Disc Brake Adaptor comes in two configurations, one that is compatible with frames with “”sliding dropouts”” and one that’s compatible with “”standard dropouts””. Both are manufactured to suit 140mm rotors. Read carefully through the fitment guide on the Specification tab to ensure you select the correct adapter for the frame type you are fitting this adapter to. 

Box Disc Brake Adapter

The all NEW Box Disc Brake Adapter is designed to help improve braking control on frames where disc brakes were not standard. Compatible with 2 types of dropouts and 3-10mm hubs, in the right configurations, the Box Disc Brake Adapter goes over your hub’s axle and mates with the frame’s dropout, allowing mounting of a standard post mount disc brake caliper. 

Please note this product is NOT universally compatible and we strongly recommend reading the Compatibility and Installation instructions for details before purchasing. 

Adapter Specifications

• Post Mount Caliper Compatibility
• 140mm Brake Rotor Only
• 6061-T6 Aluminum
• Standard 10mm Dropout – 60g
• Dropout With Insert – 65g
• Fits 3 – 10mm hubs (See Compatibility Below)
• 150lb Rider Weight Limit

Adapter Compatibility

The Box Disc Brake Adapter is NOT compatible with all frames, and purchase/installation requires special attention to your frame’s dropouts for compatibility. We do not recommend composite frames for this adapter. 

There are two different versions of the Box Disc Brake Adapter.

1. Standard 10mm Dropouts – Standard dropout configuration, dropout must be between 6-8mm thick, and have a flat inside face. Found on many frames as this is a common standard, 
2. Sliding Plate Dropout – Found on many Thrill, Haro, DK and Stay Strong aluminum frames

Both variations of the adapter come standard with two adapter rings which makes the adapter compatible with 3 different 10mm hubs only. Will not fit hubs with 15/20 or step down axles. We recommend using the Box Three Pro Disc hub as it provides the best compatibility with our adapter. Some setups with Stealth and Onyx hubs may require the dropouts spread for proper adapter fitment. 

1. Box Three Pro Disc (Needs NO adapter ring).
2. Onyx 10mm Disc (Requires O-Spec adapter ring).
3. Stealth 10mm Disc (Requires S-Spec adapter ring).

Related Components

The Box Disc Brake Adapter has many related components available from Box Components.

1. Box Three Pro Disc Hub.
2. Box Three Brake Caliper.
3. Box Three 140mm Disc Brake Rotor.
4. ALL Box Brake Levers.
5. Box Linear Brake Cables.

Box Disc Brake Adapter Installation Instructions

The Box Disc Brake Adapter requires specific installation instructions, please read all instructions for your adapter before installation.

1. Assess your hub and frame configuration. (See instructions above)
2. Select the proper components for your hub and frame.
3. Install the brake rotor onto the hub.
4. Install the adapter ring onto the hub. (If applicable)
5. Install the Brake Adapter onto the adapter ring, or hubs axle for Box Three Hubs.
6. Install the hub with brake adapter on to the frame. 
7. Ensure the adapter tabs are completely inside of the dropouts
8. Note: you must run the chain length that allows for best full engagement of the adapter on dropout. This may require a half link.

Note: some configurations may require the dropouts spread for pro proper adapter fitment.

1. Install the Caliper and align to the rotor.
2. Install the Brake Cable and adjust for desired cable pull.
3. Torque all bolts to spec, and test function of the brake.

This version is compatible with specific sliding plate dropouts with inserts. Please see the compatibility section for more details.