My uncle has his own business at his home where he works with large sheet metal forming dies. One of the tools he has always invested in is spring plungers. They come in different types depending on the type of job you are doing and how you need them. I had never seen one before until he showed me the different ones he has. He frequently orders supplies from a business on the internet. He was showing me more spring plungers that he has never needed or used. He said using these devices often makes a job much simpler.