These are the cheapest bits suitable for drilling metals and usually, come with a black coating to help prevent corrosion (when undamaged) and slightly extend life. There are several advanced coatings which extend the life of this type of bit and might help to prevent damage if you are a bit lax about cooling and lubrication.
£10.91
as of 2024-10-12 17:11
Amazon.co.uk
£9.92
as of 2024-10-12 17:11
Amazon.co.uk
13Pack HSS Twist Drill Bit Set Metric M35 Cobalt Steel High Speed Steel Titanium Coated Drill Bit...
£9.69
as of 2024-10-12 17:11
Amazon.co.uk
Last updated on 2024-10-12 17:11