SIMPLICITY • SERVICE • SATISFACTION - Sigma Sales drills, taps, abrasives, end mills, inventory Since 1977, Sigma Sales has been serving Tulsa’s cutting tool and steel supply needs. Now, with over 3000 square feet of warehouse space, we have a vast inventory of Carbide Inserts, Drills, End Mills, Taps, Abrasives and many other products in stock, ready to pick up.