A water filter includes a filter unit having a body portion adapted to be rotatingly received into a filter head assembly. An engagement protrusion extends from the body portion and is adapted for reception in a complementary receiver in the filter head assembly. An electronic device is disposed on the filter unit having a memory storage unit. A laterally extending key member is disposed on the body portion between the first engagement surface and the second engagement surface. The laterally extending key member is adapted to reposition an interference member from an interference position, whereby the body portion can be fully inserted into the filter head assembly to a non-interference position, whereby the body portion can be fully inserted into the filter head assembly.