Hole saw D. 34mm cut, T. 4mm carbide tipped with drill and spring. Promat: flat cut - carbide-tipped cutting edges allow repeated regrinding - replaceable center drill - ejector spring for the drill core for material thicknesses up to 4 mm for unalloyed steels and stainless steel up to 2 mm. From 31 mm Ø with specially hardened holder - drill body 12 mm - cutting depth 4 mm. Application note: Use high-quality cutting oil when sawing metals; do not use cutting oil when sawing cast iron and add petroleum when sawing aluminum. Further technical information: design includes drill bit and spring.