I recently bought a pair of solar panels from batteryhookup Didn’t read what they were, and just assumed they’d work. I found out the they used the MC3 connector; my system only has MC4 And the Voc was 46.2V, which in series was higher than the max VOC of my cheap solar charge controller. Not having the correct part I rigged something together; alligator clips and wire, which worked but is dangerous.