Our Insulation Plugs are made from kiln-dried white pine. They measure 3/4" thick and are slightly tapered for easy installation. One unique feature is that the top 1/8" of the plugs is straight, not tapered, to ensure a tight and even fit.  

Our Products

Tube Ends

A leaky barrel is bad for business. Luckily, we offer a high quality precise line of wood spiles to resolve those issues. Most of our spiles are 1/4" diameter and taper down to a pencil point, but we offer larger diameters as well. Available in cedar, white oak, and poplar.

Insulation Plugs

A division of Cincinnati Dowel & Wood Products Co.

Relatively new to Northern Plug's product offerings is our line of wood wedges. Also used by both coopers and distillers, our wedges are available in a variety of sizes depending on the method of repair. Although cedar is the most popular, we offer the wedges in white oak as well. 

Barrel Bungs

Wood Spiles

Our primary product line is tapered barrel bungs. We only stock the most popular diameters, however we have the ability to provide a wide range of sizes. The majority of the bungs we produce are made from face grain poplar, but we also have the ability to produce bungs in other species such as white oak, walnut, cherry, and maple. Our bungs have smooth tapered sides to ensure a perfect fit. We also offer a premium 2" bung with serrated sides which allows for an even tighter grip. 

Mortar Plugs

Wood Wedges

Tube Ends are another great product line offered by Northern Plug. Our Tube Ends are made from solid poplar, rather than compressed wood or MDF which are not as strong and can break apart. We offer sizes ranging from 1" to 6" in diameter and 7/8" thick. Whether you need to plug packing tubes, metal pipes, or other circular holes, we can surly meet your needs.

Whether you are using high-density polyethylene or cardboard tube, our mortar plugs will surely meet your needs. They are designed specifically for the firework display industry and will fit standard size tubes from 2"to 6" in diameter. They have straight sides with a chamfer on one end to allow for easy insertion and a tight fit.