Sequent Microsystems, based in Cupertino, CA, designs and manufactures I/O Expansion Cards for Raspberry Pi. Their devices expand the capabilities of Raspberry Pi with analog inputs and outputs, optically isolated inputs and outputs, on-board relays, thermistor and RTD sensor inputs, CAN and RS485 communication, and MOSFET and TRIAC drivers. Used to control up to eight loads, and stackable with up to eight to control 64 loads.