Norton MS 42 wedge burr stone. "Special order only". The Norton wedge shaped stone is a hard ceramic bond aluminum oxide "India" stone that holds its shape well but somewhat fragile in thin sections. Classified as a Medium fine grit, oil filled india burr stone. size approx.. 1' x 2.3'. We have a improved replacement composition stone in both medium fine and fine grits which is constructed using an engineered resin bond that is much less likely to chip and leaves a much smoother surface finish. We list as "wedge burr stone" in various sizes. www.specialequipment.com/product_info.php?cPath=25&products_id=116