Cobra™ Rods - Preservative Borate Rods

  • $49.99
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Add up to 15 years of life to your wood. 

With studies from 6 different internationally recognized research institutes to back it, you can trust the power of the Cobra™ Rod. 

Copper and Boron are fused together in a glass diffusible Cobra™ Rod.  When your wood is attacked by moisture, Cobra™ Rod will confidently protect it. 

A Cobra Rod is a spot treatment to decay-prone areas of logs that have already been coated with a finish. This treatment is water-soluble and protects wood against decay, fungi, and certain bugs. The Cobra Rod acts as a plug, as you can essentially drill a hole into the piece of wood, stick the rod into it, and close it up with caulk.

The Cobra Rod is superior to an Impel Rod, as the Cobra Rod is a mixture of borate AND copper hydroxide.  The additional copper hydroxide in the rod gives the Cobra Rod that extra strength to fight off wood rot, fungus, and insects.



Cobra Rods

five star


Cobra™ Rods are a way to spot treat decay-prone areas such as log ends that are already coated with a finish.

Once inserted into damp or wet wood, the borate/copper complex in Cobra Rods dissolves spreading the active ingredients into areas surrounding the rod.  This eliminates active decay fungi and helps prevent rot for 8 to 10 years.

Cobra Rods are 7/16" in diameter and are two inches in length.  A 1/2" diameter drill bit is used for installation.  The installation holes may be plugged with the accompanying plastic plugs (if available) or wood caulk.

A typical six to eight-inch round log end will require two 2” long Cobra Rods inserted within 4 inches of the butt end.


  • Great for ground-contact wood.


Use a ½” drill bit to drill hole. 

Drill hole to a depth of at least 3 ¾”. 

Clean out the hole and insert the Cobra Rod. 

Insert the plastic plug into the hole.


Using a screwdriver, twist the plug clockwise.

Make sure the top of the plug sets about ¼” below the surface of the wood.

Fill the hole with the appropriately colored wood caulk.

Smooth with tool or finger.




five star T Matthews in TN (03/02/15) - "We use cobra rods when we have soft areas in log posts and handrails to keep the rot from going any further."

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