The Manfrotto 522SCA is a standard coiled subminiphone male (2.5mm) to subminiphone male cable thats normally 25cm in length but however, it expands to 50cm when uncoiled. Its an available option for the electronic shutter release of the 322RC2 grip action ball head, and also a replacement remote for the 521, 522 and 523 remote controllers.

This is the 'stereo' version of the subminiphone cable; some 2.5mm devices don't need the 'stereo' function of the plug, but it would likely still function normally with them. There are quite a number of various products on the photographic market which employ this 2.5mm subminiphone connection.