Siemens 406-2B 3.88 Card, a 15-point interface control circuit board. This refurbished replacement from the Siemens 406-2B family is designed for legacy automation equipment that uses the 15-point interface, with revision 3.88 identified in the model name (406-2B3.88). The listing positions it as a drop-in replacement part suitable for Siemens control panels and older automation hardware that rely on the 406-2B series for I/O interfacing. Sold as a refurbished module by providers such as York Controls, it is described specifically as the Siemens 406-2B3.88 card.
