The PCLD-785 carries 16/24 SPDT electromechanical relays with a 20-pin flat cable connector and an additional 50-pin Opto-22 connector (for PCLD-785B only) compatible with the digital outputs of most I/O Cards. The number of output channels available on the PCLD-785B depends on the connector you use. The I/O card’s 50-pin connector accesses all 24 channels, while its 20-pin connector has access to 16 channels.