We tried felt casters but the furniture slid around when you sat down so we got these at Lowes. It says they are safe for hardwood. No sliding at all. Our furniture legs are black squares and these blend in with the hardwood so they’re not that noticeable.

Thank you both for your input! (Why didn't Houzz notify me of these comments? Had to find them via the 'posts I started' on my profile page. Ugh.)

@Joaniepoanie, we use this type of floor protection for beds and sofas. They do the job indeed. Put them on the bed casters too late though - the damage was done. @3katz4me is right: I meant rolling casters (for my desk chair). And you're absolutely right, 3katz, any particles being rolled around on the floor can damage it. I need to be mindful of vacuuming my space regularly. The current chair casters are plastic and ruined the floor finish in a spot. I've since been using a small rug but would rather solve the issue at the root as I'm not fond of rugs in my office. I've read it's best to use rubber or polyurethane casters on hardwood. Apparently those akin to rollerblade wheels do the trick.

I always recommend 'canister' rollers - the one's shaped like soup cans with a slightly grip. Stay AWAY from 'rubber'. Rubber can STAIN hardwood and vinyl. The polyurethane ones are fine.

Good luck.

Is this the kind you mean, @SJ McCarthy?

Yep. Exactly! The light gray indicates a soft(er) surface and the double wheels reduce the pounds per square inch to reduce the pressure applied on the floor.

I should see if I can get those for DH’s office chair (from one of those big-box office stores). We ended up getting a pad to go under it once I saw the damage.

Thank you, SJ! Ordered a set.

Installed them yesterday and so far, so good!! (They might roll too easily. :P) Really hope these work because I do not want a rug in the space.