This listing is for a set of 4 all stainless steel M12 x 51mm long leveling mounts from S & W Manufacturing.  These are high quality 316 Stainless Steel that will resist corrosion and rusting.  These were purchased for a project that was never finished.  3 of the leveling feet are still unopened in packaging, and the 4th was only opened to take photos.  These are the same as McMaster Carr part number 6301K34 if you need additional dimensions.  These list for $45-$60 each on industrial websites.  Please feel free to send me a message for any additional information.