These are a great product to protect your chair legs and offer extra glide on hard surfaces. Longevity will tell how durable they are but I have plenty extra just in case. The round product works well on the square chair leg, with no issues at all.
I bought to redo some very comfortable yet very old chairs I have. I knew it was going to be a little big on the legs so I use gorilla glue to fill in the gaps. They look great and protect my floor from the metal chair legs. I put new upholstery on the chair and painted the bronze legs.
I have metal dining room chairs and over the years I’ve bought adhesive felt pads, silicone pads. All would work for a while and then fall off. These look more durable. I had 4 chairs, so I bought 32 pieces for replacement parts. Important to measure your items to make sure they are the right size.