Rappel rack

Rappel racks, also known as abseil racks, are a type of descender. They are often used in caving, where they are valued for their versatility and excellent friction control. Though similar designs have been in use since at least 1876, the modern rack was developed independently by both John Cole and Warren Lewis, who both released their designs in 1969. The basic design used in modern racks remains much the same as the ones designed in 1969.