These hole saws have special gulleted square teeth coated in a tungsten carbide or silicone carbide grit which allows them to cut through hard and abrasive materials quickly.

Their square teeth do not "bite" into the material as standard curved saw teeth do. This allows them to cut into harder materials (like ceramic or glass) without shattering them. 

Long-lasting choice for very hard abrasive materials. These hole saws create clean holes in materials too hard or abrasive for standard bi-metal saws, or so thin they would strip bi-metal or chip carbide teeth. Cutting depth of 1-1/2" (38mm). Arbor required.

Features & Benefits
1. Super resistance to heat, wear and abrasion with shock resistant back
2. Tungsten carbide grains are bonded to alloy backs with a gulleted snag resistant edge TCT pilot drill recommended for masonry type materials