The beauty of timber, powerfully protected. CUTEK® Extreme is a professional-grade, oil-based wood stabilizer engineered in Australia for the world's harshest climates — and the gold-standard finish for premium thermally-modified and naturally durable wood.

How CUTEK® Extreme Works

Unlike traditional surface coatings, CUTEK® Extreme penetrates and diffuses deeply into the wood core and stays permanently mobile inside the wood. This unique self-healing action lets the oil migrate back to any cut, scratch, or fastener perforation — protecting your wood from the inside out.

By controlling both liquid and gas-phase moisture, CUTEK® Extreme dramatically improves dimensional stability, reducing warping, cupping, and splitting. The result is wood that lasts longer, looks better, and ages on your terms.

Why CUTEK® Extreme

• Stabilizes Your Wood — significantly reduces splitting, warping, and cupping
• Self-Healing Effect — stays mobile inside the wood and migrates to cuts and perforations
• No Flaking or Peeling — designed to fade gracefully with time, not lift off
• Easy Maintenance — no sanding or stripping required, just clean and recoat
• Cost Effective — up to 2× the coverage rate of most wood coatings (approximately 400 SF per gallon)
• Enhances Natural Beauty — applied clear, your wood is the star
• CUTEK® Cares — one tree planted for every can of CUTEK® Extreme sold

Pre-Finishing at the Mill

For best results, we recommend pre-finishing CUTEK® Extreme at the time of milling. Pre-finishing delivers the most consistent absorption, fully coats all six sides of each board (including end grain), and reduces field labor. Add finish to any milled lumber order at $1.25/LF — note this preference at checkout.

Typical Applications

CUTEK® Extreme is appropriate for all exterior wood applications including decking, siding, fencing, sauna exteriors, and trim. Not recommended for food-preparation surfaces, wood in direct ground contact, or engineered bamboo products.

Tint It Your Way with CUTEK® Colortone

Applied as a clear oil, CUTEK® Extreme lets your wood naturally silver over time. Mix in any of 18 CUTEK® Colortones (sold separately) to maintain the freshly-oiled tone or shift the color to suit your design — one 3 oz Colortone can tints one gallon of CUTEK® Extreme.