This is probably the number one tool we get questions about on The Fab Forums YouTube channel.
The Cleco...this things come in different sizes and versions but they all do the same thing. They are designed to temporarily hold Sheetmetal together. Most of the time they are replaced by rivets or sheet metal screws during final assembly.
The best part is that these things are very affordable.
Cleco Kit - https://amzn.to/2R1eT9Y
Cleco Clamps - https://amzn.to/2QYoZbF
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