TiN Tianium Nitride Coated Drill Bits are Drill Bits suited for drilling stainless steel. Superhard titanium nitride surface treatment improves drill life, chip ejection, and productivity. Tin Coated Drill Bits for sale by Bisco are ideal for hard metals, work hardened stainless steel and other difficult to drill metals. Tin Coated Drills are Jobber Length and sold in Fractional and Wire Gauge Sizes.