The invention proceeds from a top-lock wiper blade adapter for coupling a wiper blade to a corresponding top-lock wiper arm adapter (10), having at least one main body (12) and at least one locking element (14) which is provided for locking the main body (12) to the top-lock wiper arm adapter (10). It is proposed that the top-lock wiper blade adapter has a blocking unit (16), which comprises at least one engagement element (18, 20) which engages at least partially over at least one inner abutment surface (22, 24) of the main body (12) and is provided to avoid the locking of a top-lock wiper arm adapter (26) which deviates from the corresponding top-lock wiper arm adapter (10) in terms of width (28).