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Montolit FAJ08 5/16" Diamond Drill Bit

Montolit FAJ08 5/16" Diamond Drill Bit

by Montolit
SKU FAJ08
$35.89 - $35.89
$35.89
$35.89 - $35.89
$35.89

Clean, fast holes in the hardest tile. The Montolit FAJ08 5/16" Diamond Drill Bit drills a 5/16" hole through dense porcelain, natural stone, and glass with a vacuum-brazed diamond crown that bites hard and leaves crisp edges — far less chipping and cracking than cheap bits. Run it wet or dry, on a drill or a grinder.

More Details

A vacuum-brazed diamond drill bit for clean 5/16" holes in porcelain, stone, and glass.

  • Hole size: 5/16"
  • Diamond crown: Vacuum-brazed for aggressive cutting and clean hole edges
  • Materials: Dense porcelain, natural stone, glass, and other hard tile
  • Wet or dry: Works either way — adapts to any jobsite setup
  • Best for: Small-diameter anchors and detail holes in dense porcelain and polished stone
  • Build: Balanced body runs with minimal vibration for accurate starts and straight holes
Shipping & Return Policies

Shipping Policy

Refund & Return Policy

Montolit FAJ08 5/16" Diamond Drill Bit — Detail Holes That Stay Sharp

The in-between sizes are where cheap bits quit early — a 5/16" hole in dense porcelain or polished stone loads up the crown and glazes it before the job's done. The Montolit FAJ08 holds its edge, driving a clean 5/16" hole with a vacuum-brazed diamond crown that keeps cutting where lesser bits burn out, leaving crisp edges on the hard, glossy material that punishes rough work.

It runs wet or dry, on a drill or an angle grinder, and starts accurately thanks to a balanced body. For dry drilling, keep it alive with a dip of M-PERFORMER cooling gel, and finish the opening with the Diamond Countersink to bevel the edge and relieve stress.

Why Tile Pros Choose It

  • Holds its edge: Vacuum-brazed 5/16" crown keeps cutting on dense material
  • Hard materials: Dense porcelain, polished natural stone, and glass
  • Wet or dry: Drill or grinder to fit the job
  • Accurate starts: Balanced body for straight, clean holes
  • Best for: Small-diameter anchors and detail holes in dense porcelain and polished stone
  • Outlasts the bargain bin: The cheap one dies mid-hole; this one finishes the job

Pro tip: Keep the bit moving in a slight circular motion once you're through the glaze — it clears debris and keeps the crown cooler than boring straight down in one spot.