The sliders are sturdy and well made, but in installing them I had to do some drilling and in an effort to clean out any possible flakes of material that might have gotten into the track I used a can of brake cleaner which started to melt the plastic material that holds the ball bearings in place. My fault for getting material in the unit that needed to be removed... but I'm disappointed that a plastic was used in the product that will melt with brake cleaner, a very commonly used cleaning agent for industrial purposes.DO NOT USE BRAKE CLEANER to clean the tracks.