File:Carbon-fluorine-bond-polarity-2D.png - Wikipedia
Polarity symbols - Wikidata
Plus Positive Polarity Symbol Sign Isolate on White Background,Vector Illustration EPS.10 Stock Vector - Illustration of minus, generation: 155800988
Please make focus symbols uniform with their polarity equivalent or atleast similar. e.g. I could see the Naramon polarity be a simplified version of the Zenruik focus symbol. : r/Warframe
Power Supply Symbols
power supply - Polarity symbols on universal AC-DC adaptor - Electrical Engineering Stack Exchange