A mechanical model of a PR-Box

Several mechanical realizations of PR-Boxes are discussed. Apart from superluminal correlations, which are known not to be realizable by classical devices, the requirements (1) PR-condition on input-output relations, (2) non-signaling, and (3) allowing for independent measurements are discussed separately. The examples show that internal signaling (inside the box) does not invariably imply the possibility of external signaling and may externally be attributed to contextuality. The proposed model requires two classical bits to be exchanged internally in order to realize the defined requirements. However, with EPR correlations this can be reduced to one classical bit.