USB HID Quad Relay output and Quad Optoisolator input module.
This boards controls 4 relays and 4 input optoisolators.
Each relay as 3 connections (NO, C, NC).
Each relay can switch 2A at 30VDC and 0.6A at 125VAC.
Relay mapping:
P1.4 -> Relay1, P1.5 -> Relay2, P1.6 -> Relay3, P1.7 -> Relay4 (Relays active low)
Optocoupler inputs are tied to P0.0-3 and are active from 2 to 60 volts.
The Optocoupler part number used is TOSHIBA TLP293-4(GB,E

Powered and controller via the USB port.
Dimensions: 2.5"x2.0"
Schematic
PCB