A rotatable connection for a stand apparatus for arrangement in an operating room, including an adjustable stop mechanism, which can be arranged between a first connection component and a second connection component mounted rotatably about a rotational axis relative to the first connection component and which is configured to define different rotational angles or rotation ranges of the connection components relative to each other. The adjustable stop mechanism includes: a stop ring which can be mounted to the first connection component in an anti-rotational manner, an anti-rotation device, a stop device with a counter stop, and a rotary block. The stop device can be positioned at the anti-rotation device in different rotational angle positions in an anti-rotational manner. A support system or a stand apparatus with such a rotatable connection and a method for adjusting the adjustable stop mechanism are provided.