Heavy duty, and I mean heavy. It would take a lifetime to wear these shoes out. I don't favor the bolt that secures each shoe to the bucket--the nut that contacts the bucket doesn't freewheel, so the shoe tends to wander as you tighten it, unless you firmly hold the shoe. This is not a deal breaker, as the design dimensions are spot on and the welds look good.They fit the bucket on my Yanmar SA221 and my Kubota BX25D. I use the Yanmar to push gravel back level on a parking lot that sees truck traffic and a mail lady who manages to spin her wheels every day. The shoes keep me from making things worse! I didn't get anything for this review.