The invention provides an adaptor for mechanically coupling a prompt box and a video camera to a tripod. In the preferred embodiment, the adaptor is a single piece bracket having a first horizontal portion with a first fastening round hole located at the first horizontal portion's center, a vertical portion with its lower end merged to the first horizontal portion, and a second horizontal portion merged to the vertical portion's upper end. The second horizontal portion has one or more second fastening round roles evenly spaced along the second horizontal portion's longitude. In operation, the prompt box is fastened to the tripod through the first fastening round hole, and the video camera is fastened through one of the second fastening round holes with a screw matching the video camera's tripod mount.