Developed to drill holes for rivets in flat and curved panels and are ideal for use in car body work and sheet metal fabrication Popular for pop-rivet drilling applications Cobalt increases the strength of the steel and makes it more heat-resistant; this is an important factor in drilling hard materials because the friction of metal against metal can produce high temperatures that damage the material or the drill bit Fully ground M35 HSS material increases drill life Precision engineered shank for accurate hole size Quick and efficient swarf clearance allows clog-free precision drilling.