From Manufacturer
The Zacuto QR Shoulder Pad is shaped to fit comfortably on your shoulder, providing a quick release (QR) camera-mounted pad to cushion your shoulder from the camera. The gel pad cushion is made from Akton Polymer, which absorbs shock and vibration and retains its properties in temperature extremes far exceeding what you or I could tolerate.
The included QR plate attaches to a camera or baseplate, and you slide the plate into the QR clamp on the shoulder pad. This allows you to easily adjust the camera's position on the shoulder pad for balance and comfort. The QR system also allows you to quickly remove the shoulder pad and mount the camera to a tripod with a compatible QR mechanism.