The following review is for the Dynaplug tool.  This item is for the refill for that tool. The refills will store readily inside the handle.After living in Downtown Los Angeles for over 2 years, I have had about 5 bouts of tire leaks due to punctures.  Before I found out about this product, I used the traditional DIY method of repairing my tire--with a kit I got at Pep Boys.  It was always an exhausting, time consuming process.  I'm not a very strong person and most of the punctures were with small objects (pallet nails, staples). Imagine having to stuff a thick, dull rasp tool through extremely thick tire tread.. Not fun.  Threading a thick rubber embedded cord through a very thin slot was always a pain in the butt too.  Always ended up having to fumble with needle nose pliers to pull it through requiring  several tries.Along comes this product. All I can say is WOW!!!  Slick it up, insert the little plug into the tool, slick up the tool and hole with some more spit, and push it in.  The tool is smooth and goes in with way less effort.  Pull it out and snip the remainder.  Done!  By a very large margin, the absolute EASIEST tire repair tool you will EVER use.For *extremely* small holes, it can still require a bit of effort, but no where near the unimaginable effort that would have been required of the typical rasp and thread-end tools.  Just be sure to use spit.  (Water doesn't work nearly as well).Summary:PROS:-Makes repairing the smallest leaks much easier.-Fast.  Can repair a tire in half the time.  Some have even repaired their tires without removing them.-Permanent. Dynaplugs have been approved in Europe for permanent tire repair.-Use way less strength.  Only a single tool, and it is very thin.-Convenient storage in handle for extra plugs, and the pipe cleaner. There is enough room to even store a couple of small alchohol swabs in it.-Can be used to repair previous traditional plugs that have failed.-Fool proof.  Awesome design allows you to push the tool in ALL THE WAY, and pull out.  Traditional plugging can be pushed in too far or not far enough.-Can repair other failed patches.-Versatile.  Dynaplug can be applied multiple times to the same hole to repair larger holes.CONS:-The tool may get dirty on the inside and be hard to insert additional plugs in the same session.  The tool comes with a felt pipe cleaner which can be dabbed in alcohol to clean the inside.  Best way to avoid this is to ensure the plug and tool is well lubricated.