40pcs Round Heavy Duty Nail-on Anti-Sliding Felt Pad for Furniture Chair Table Leg Feet Floor Protectors (Brown, 18mm)

Q: Has anyone used these with patio furniture on a wood deck? My current teak furniture -- which has plastic caps on the legs -- leaves scratches.

If your flooring has a fine finish and the spaces between the planks are narrow, you should be fine using these. We use them on our DR furniture legs which slide on our hardwood floor. They work very well. Keep an eye on how they're wearing so you're prepared to replace as needed. Don't have a 'lasts-a-really-long-time' item for a substitute.

Q: What does the mm represent on the size? Is it the radius of the pads or the thickness of the height?

MM represents the diameter of the pads. The diameter in inches .69 inches or 11/16th of an inch per my measurement of the pad. 12/16 would have been 3/4 ths of an inch