EZ Off Jar Opener for Seniors - Under Cabinet Jar Openers for Weak Hands, Easy Grip, Arthritis jar opener, One Handed Gadgets & Bottle Opener - Essential Kitchen Gadgets for Home Assistance - White

I installed an under-counter one like this before I had shoulder surgery a few years ago, knowing I’d be largely one-handed for a while. Works great, although it does sometimes roughen up the edges of the jar lids a bit. Other models might be gentler than mine? https://a.co/d/0dQIe4H0

https://www.amazon.com/dp/B000X6K9J8 This is much simpler and easier to use and works incredibly well. My elder inlaws use it for opening jars.