Review on 🔧 Efficiently Assemble Your RENOGY Solar Panels with this Connector Assembly Tool by Dave Knain

These keys do not fit all MC4 connectors. I bought Revain Prime MC4 connectors and these keys. The wrenches slipped off the gland nut when trying to assemble and tighten the connectors. They slipped so much I could tighten them tighter than wrenches. I was about to return the keys when I realized that Renogy also makes MC4 connectors. So I bought a set of Renogy plugs and the keys fit perfectly. Renogy connectors use a torx wrench-like lobed gland nut, which provides an excellent way to engage the tool with the nut. So the key does not slip on the nut at all when tightening. I only took off one star because I think the product description should include a note that these wrenches are for Renogy connectors and may not work with other MC4 connectors. I was misled by the product description that the MC4 is standard and this key fits all MC4 connectors. By the way, the Renogy plugs seem to be of a higher quality than other plugs I have bought and the contact material has better silver plating. Anyway, I hope this helps you avoid my mistake. I'm fairly new to many affordable solar manufacturers, but my experience with Renogy has been positive so far.