Ski binding

A ski binding is a device that connects a ski boot to the ski. Generally, it holds the boot firmly to allow the skier to maneuver the ski. However, if certain force limits are exceeded, it releases the boot to minimize skier injury, such as in the case of a fall or impact. There are different types of bindings for different types of skiing.

Modern alpine skiing bindings fix the boot at the toe and heel.

In some bindings, to reduce injury the boot can release in case of a fall. The boot is released by the binding if a certain amount of torque is applied, usually created by the weight of a falling skier. The torque required is adjustable, according to the weight, foot size, and skiing style. A snow brake prevents the ski from moving while it is not attached to a boot.

Also known as randonee, an alpine touring binding allows the heel to be clipped down to the ski when skiing downhill, but allows it to be released when climbing.

An alpine touring binding allows the skier to have the heel of the ski boot free and the toe of the ski boot in the binding when using Nordic skiing techniques for ski touring, and to have both the heel and the toe of the ski boot in the binding when using alpine skiing techniques to descend the mountain. Most touring bindings are designed for ski boots falling under one of two ISO specifications:

The two setups are mutually incompatible: in the former, the boot lacks sockets to engage ISO 9523 compatible bindings, while the later boot toe and heel-piece dimensions are incompatible with ISO 5355 bindings.

The cable binding was widely used through the middle of the 20th century. It has the toe section of the boot anchored, and an adjustable cable around the heel secures the boot. While binding designs vary, before 2007 almost all dedicated Telemark models had been designed to fit boots with 75mm Nordic Norm "duckbill" toes.

The Rottefella binding was developed in 1927 by Bror With. The name means "rat trap" in Norwegian. It is also known as the 75 mm, Nordic Norm, or 3-pin. After victories at the 1928 Winter Olympics in St. Moritz, the binding remained the standard for cross-country skiing for the next 60 years. They are no longer as popular as they were but are still for sale. The binding has three small pins that stick up from the binding. The toe of the boot has three holes into which the pins are inserted. The boot is then clamped down by a bail. The binding is asymmetrical, having left and right foot orientations.

...
Wikipedia