A spring-loaded camming device (also SLCD, cam or friend) is a piece of rock climbing or mountaineering protection equipment. It consists of two, three, or four cams mounted on a common axle or two adjacent axles, so that pulling on the axle forces the cams to spread further apart.

The ZCam supplements full-color video camera imaging with real-time range imaging information, allowing for the capture of video in 3D.

Micro-cams are defined here as smaller than 2/3 inch (17mm) at their widest range—such cams' effective range maxes out at around 1/2 inch (13mm) or fin- gertip size. These cams are rated to significantly lower strength than their larger siblings (up to 50 percent less).

The camming angle is the angle at which the force is applied and is defined as the angle made between the radius of the spiral and the line tangent to the spiral at the intersection point (figure on the right). The camming angle determines the range and holding power of the cam.