Tools and warning signs

I use this cylinder without the ring seal. It is designed to be able to do so. The flange is wider to provide a better seal. And is comfortable. And if the slide happens of a nut being sucked in like mentioned previously. Just release pressure and reposition. The pic is not my recommendation as in measurement for you, just a pic to show you the design. There are several sizes available. This is the link to the site I use. Pumps - ManShop