Replaced a LED in this. We have similar heads with the double diamond, but no other names or markings. Someone one another site says those are made by Checker Signal, never heard of Checker. Says Garland TX
I dont know where the checker name came from but there is a model that is identical to that without signal computer corp on it. Just double diamonds. They are supposably a poor quality casting but aluminum McCains are much worse. The half dozen or so I see. Up close were all in decent shape give or take some internal corrosion