Hymnorq 10-Piece 1/4 Inches Cobalt Drill Bit Set – M35 Grade (5% Cobalt) Steel, Fully Ground, Dual Twist Flute, 135 Degree Split Point, Jobber Length, Bronze Finish, with Tough PP Storage Case;

OVERVIEW
Different types of drill bits are used to cut holes in different types of materials. This set of M35 cobalt steel drill bits are particularly successful in cutting through hard metals such as stainless steel and cast iron, although they can be used for softer materials, too.
Cobalt drill bits are not made of pure cobalt, but rather a steel alloy with certain percent cobalt. The 5-percent alloy is known as M35 grade. The 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.
Tests shows that the M35 cobalt steel drill bits can penetrate a 5mm-thick 304 stainless steel plate in 5 seconds.
Cobalt drill bits are more expensive than other drill bits, but if you regularly drill through metal, they are a good investment since they tend to last longer. With an extended tool life, Hymnorq cobalt drill bits will give you the lowest cost per hole drilled.

NOTICE: Please use with cooling liquid to prolong the working life of the drill bits and to avoid overheating and breakage.
This set M35 grade cobalt drill bits are not suitable for hardened steel / high carbon steel.

TECHNICAL DETAILS:
Material: M35 Cobalt Steel
Angle Point: 135 Degree
Flute Type: Spiral
Hardness: Rockwell 67
Shank Type: Straight Shank

WHAT'S INCLUDED:
1/4" Cobalt Steel Drill Bit x 10pcs
Plastic Case x 1pc

BUY WITH CONFIDENCE:
If you're not completely satisfied with the product quality, please contact us. Refund or free replacement.