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Gear

The ABC's of AFD and DIN

Gear

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The AFD, or antifriction device, that our boot soles ride on just behind the toepiece, is a key part of the release system. It helps the boot to release from the toepiece consistently, no matter what kind of load is placed on that system, and regardless of what kind of ice, snow, dirt, or other stuff might be in and around the connection between boot and binding. AFDs come in two main varieties. A fixed AFD relies on the slippery nature of the material it’s made of (usually Teflon) to allow the boot to slide out of the toepiece. A mechanical AFD utilizes a rolling or gliding aparatus to promote the boot’s smooth exit from the binding. Tests have shown both types to be effective, although mechanical AFDs tend to be the most consistent. Regardless, to help the binding do its job, you should keep your binding and boot sole as clean and free of snow, ice, and dirt as possible.

The so-called DIN range indicates how much force is required to open, or release, the toepiece or heelpiece. Based on your height, weight, age, boot-sole length, and skier type, a technician can determine your numerical setting for a given binding. This number should be near or above the midpoint of the binding’s DIN range. For example, if the technician determines your setting is a 7, a DIN range of 3-10 would be appropriate. If it turns out that our specific binding picks here don’t match your setting needs, use our choices as a guide to the features you’ll want to find in a more suitable model.