A hot shoe is a mounting point on the top of a camera to attach a flash unit and other compatible accessories. It takes the form of an angled metal bracket surrounding a metal contact point which completes an electrical connection between camera and accessory for standard, brand-independent flash synchronization.
The hot shoe is a development of the standardised "accessory shoe" or "cold shoe", with no flash contacts, formerly fitted to cameras to hold accessories such as a rangefinder, or flash connected by a cable.
The dimensions of the hot shoe are defined by the International Organization for Standardization (ISO) in ISO 518:2006. Details such as trigger voltage are not standardised; electrical incompatibilities are still possible between brands.[1]