I have some arthritis in my hands, which makes it difficult to open jars, bottles, etc.  I got this OXO Good Grips Jar Opener with base and should’ve gotten it a long time ago!  It has saved my hands!  The included Base is for placing the item you’re opening on, to help keep it from slipping while opening it with the jar opener. This OXO Jar Opener works on all sizes of jars. I recommend this handy little gadget for anyone that has trouble opening jars.