Typical 1960s era circuit board designed and manufactured at Chalk River for use in nuclear physics research experiments. The boards, typically 19 cm in length, with a handle at the rear, would plug into a header that supplied the data signals as well as the operating power for the board. Thes units predated the NIM (Nuclear Module Instrumentation) modules which became standard in the early 1970s. This board was part of the electronics instrumentation used by Warwick Knowles at Chalk River.